Expand and Contract












19












$begingroup$


Take a positive integer $k$ as input. Start with $n := 1$ and repeatedly increase $n$ by the largest integer power of ten $i$ such that $i le n$ and $i + n le k$.



Repeat until $n = k$ and return a list of all intermediate values of $n$, including both the initial $1$ and the final $k$.



During this process, growth will initially be limited by the former inequality, and only afterwards by the latter; the growth will take the form of an initial "expansion" period, during which $n$ is increased by ever-larger powers, followed by a "contract" period, during which $n$ is increased by ever-smaller powers in order to "zoom in" on the correct number.



Test Cases



1 => [1]
10 => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
321 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 310, 320, 321]
1002 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 400, 500, 600, 700, 800, 900,
1000, 1001, 1002]


This is code-golf, so the shortest answer (in bytes) wins.










share|improve this question









$endgroup$








  • 2




    $begingroup$
    May we print the numbers instead of returning a list?
    $endgroup$
    – Adám
    Apr 3 at 8:01










  • $begingroup$
    @Adám Yes, you may.
    $endgroup$
    – Esolanging Fruit
    Apr 3 at 16:32
















19












$begingroup$


Take a positive integer $k$ as input. Start with $n := 1$ and repeatedly increase $n$ by the largest integer power of ten $i$ such that $i le n$ and $i + n le k$.



Repeat until $n = k$ and return a list of all intermediate values of $n$, including both the initial $1$ and the final $k$.



During this process, growth will initially be limited by the former inequality, and only afterwards by the latter; the growth will take the form of an initial "expansion" period, during which $n$ is increased by ever-larger powers, followed by a "contract" period, during which $n$ is increased by ever-smaller powers in order to "zoom in" on the correct number.



Test Cases



1 => [1]
10 => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
321 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 310, 320, 321]
1002 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 400, 500, 600, 700, 800, 900,
1000, 1001, 1002]


This is code-golf, so the shortest answer (in bytes) wins.










share|improve this question









$endgroup$








  • 2




    $begingroup$
    May we print the numbers instead of returning a list?
    $endgroup$
    – Adám
    Apr 3 at 8:01










  • $begingroup$
    @Adám Yes, you may.
    $endgroup$
    – Esolanging Fruit
    Apr 3 at 16:32














19












19








19





$begingroup$


Take a positive integer $k$ as input. Start with $n := 1$ and repeatedly increase $n$ by the largest integer power of ten $i$ such that $i le n$ and $i + n le k$.



Repeat until $n = k$ and return a list of all intermediate values of $n$, including both the initial $1$ and the final $k$.



During this process, growth will initially be limited by the former inequality, and only afterwards by the latter; the growth will take the form of an initial "expansion" period, during which $n$ is increased by ever-larger powers, followed by a "contract" period, during which $n$ is increased by ever-smaller powers in order to "zoom in" on the correct number.



Test Cases



1 => [1]
10 => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
321 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 310, 320, 321]
1002 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 400, 500, 600, 700, 800, 900,
1000, 1001, 1002]


This is code-golf, so the shortest answer (in bytes) wins.










share|improve this question









$endgroup$




Take a positive integer $k$ as input. Start with $n := 1$ and repeatedly increase $n$ by the largest integer power of ten $i$ such that $i le n$ and $i + n le k$.



Repeat until $n = k$ and return a list of all intermediate values of $n$, including both the initial $1$ and the final $k$.



During this process, growth will initially be limited by the former inequality, and only afterwards by the latter; the growth will take the form of an initial "expansion" period, during which $n$ is increased by ever-larger powers, followed by a "contract" period, during which $n$ is increased by ever-smaller powers in order to "zoom in" on the correct number.



Test Cases



1 => [1]
10 => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
321 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 310, 320, 321]
1002 => [1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 20, 30, 40, 50, 60, 70, 80, 90,
100, 200, 300, 400, 500, 600, 700, 800, 900,
1000, 1001, 1002]


This is code-golf, so the shortest answer (in bytes) wins.







code-golf number decimal






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Apr 3 at 5:05









Esolanging FruitEsolanging Fruit

8,73932776




8,73932776








  • 2




    $begingroup$
    May we print the numbers instead of returning a list?
    $endgroup$
    – Adám
    Apr 3 at 8:01










  • $begingroup$
    @Adám Yes, you may.
    $endgroup$
    – Esolanging Fruit
    Apr 3 at 16:32














  • 2




    $begingroup$
    May we print the numbers instead of returning a list?
    $endgroup$
    – Adám
    Apr 3 at 8:01










  • $begingroup$
    @Adám Yes, you may.
    $endgroup$
    – Esolanging Fruit
    Apr 3 at 16:32








2




2




$begingroup$
May we print the numbers instead of returning a list?
$endgroup$
– Adám
Apr 3 at 8:01




$begingroup$
May we print the numbers instead of returning a list?
$endgroup$
– Adám
Apr 3 at 8:01












$begingroup$
@Adám Yes, you may.
$endgroup$
– Esolanging Fruit
Apr 3 at 16:32




$begingroup$
@Adám Yes, you may.
$endgroup$
– Esolanging Fruit
Apr 3 at 16:32










15 Answers
15






active

oldest

votes


















7












$begingroup$


Haskell, 72 68 64 63 bytes





f=(1!)
c!t|t==c=[c]|t>c=c:(c+10^(pred.length.show.min c$t-c))!t


Try it online!



Thanks Sriotchilism O'Zaic for -4 bytes!



Usage



f 321
[1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100,200,300,310,320,321]


Explanation



c!t         -- c=current number, t=target number
|t==c=[c] -- Target is reached, return last number
|t>c=c:(c+10^(pred.length.show.min c$t-c))!t
c: -- Add current number to list
min c$t-c -- The minimum of the current number, and the difference between the current number and the target
length.show. -- The length of this number
pred. -- Minus 1
10^( ) -- Raise 10 to this power
c+ -- Add that to the current number
( )!t -- Recursion





share|improve this answer










New contributor




Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






$endgroup$









  • 4




    $begingroup$
    Welcome to PPCG! Nice first answer.
    $endgroup$
    – Arnauld
    Apr 3 at 9:13






  • 2




    $begingroup$
    I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
    $endgroup$
    – Kevin Cruijssen
    Apr 3 at 9:21








  • 2




    $begingroup$
    Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
    $endgroup$
    – Sriotchilism O'Zaic
    Apr 3 at 13:24








  • 1




    $begingroup$
    pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
    $endgroup$
    – Laikoni
    Apr 4 at 9:27






  • 1




    $begingroup$
    Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
    $endgroup$
    – Laikoni
    Apr 4 at 9:37



















6












$begingroup$

JavaScript (ES6), 50 bytes



f=n=>n?[...f(n-(1+/(^10)?(0*$)/.exec(n)[2])),n]:


Try it online!



How?



Theory



The following steps are repeated until $n=0$:




  • look for the number $k$ of trailing zeros in the decimal representation of $n$

  • decrement $k$ if $n$ is an exact power of $10$

  • subtract $x=10^k$ from $n$


Implementation



The value of $x$ is directly computed as a string with the following expression:



+---- leading '1'
|
1 + /(^10)?(0*$)/.exec(n)[2]
____/___/
| |
| +---- trailing zeros (the capturing group that is appended to the leading '1')
+--------- discard one zero if n starts with '10'


Note: Excluding the leading '10' only affects exact powers of $10$ (e.g. $n=color{red}{10}color{green}{00}$) but does not change the number of captured trailing zeros for values such as $n=color{red}{10}23color{green}{00}$ (because of the extra non-zero middle digits, '10' is actually not matched at all in such cases).






share|improve this answer











$endgroup$













  • $begingroup$
    Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
    $endgroup$
    – Ørjan Johansen
    Apr 4 at 17:36





















3












$begingroup$


Python 2, 61 bytes





f=lambda k,n=1:n<k and[n]+f(k,n+10**~-len(`min(n,k-n)`))or[n]


Try it online!






share|improve this answer











$endgroup$





















    2












    $begingroup$


    Perl 6, 48 41 bytes





    ->k{1,{$_+10**min($_,k-$_).comb/10}...k}


    Try it online!



    Explanation:



    ->k{                                   }  # Anonymous code block taking k
    1, ...k # Start a sequence from 1 to k
    { } # Where each element is
    $_+ # The previous element plus
    10** # 10 to the power of
    .comb # The length of
    min($_,k-$_) # The min of the current count and the remainder
    /10 # Minus one





    share|improve this answer











    $endgroup$





















      2












      $begingroup$


      APL (Dyalog Unicode), 30 bytesSBCS





      Anonymous tacit prefix function. Prints numbers on separate lines to stdout.



      {⍺=⍵:⍺⋄⍺∇⍵+10*⌊/⌊10⍟⍵,⍺-⎕←⍵}∘1


      Try it online!



      {}∘1 anonymous infix lambda with 1 curried as initial $n$:



      ⍺=⍵ if $k$ and $n$ are equal:



         return (and implicitly print) $k$



        else:



        ⎕←⍵ print $n$



        ⍺- subtract that from $k$



        ⍵, prepend $n$



        10⍟$log_{10}$ of those



         floor those



        ⌊/ minimum of those



        10* ten raised to the power of that



        ⍵+$n$ plus that



        ⍺∇ recurse using same $k$ and new $n$








      share|improve this answer









      $endgroup$





















        2












        $begingroup$


        05AB1E, 15 bytes



        1[=ÐIαD_#‚ßg<°+


        Port of @PaulMutser's (first) Haskell answer, so make sure to upvote him!!



        Try it online or verify all test cases.



        Outputs the numbers newline delimited.

        If it must be a list, I'd have to add 3 bytes:



        X[DˆÐIαD_#‚ßg<°+}¯


        Try it online or verify all test cases.



        Explanation:





        1             # Push a 1 to the stack
        [ # Start an infinite loop
        = # Print the current number with trailing newline (without popping it)
        Ð # Triplicate the current number
        Iα # Get the absolute difference with the input
        D # Duplicate that absolute difference
        _ # If this difference is 0:
        # # Stop the infinite loop
        ‚ß # Pair it with the current number, and pop and push the minimum
        g<° # Calculate 10 to the power of the length of the minimum minus 1
        + # And add it to the current number





        share|improve this answer











        $endgroup$





















          1












          $begingroup$


          Jelly, 19 bytes



          1µ«³_$DL’⁵*$+µ<³$п


          Try it online!






          share|improve this answer









          $endgroup$





















            1












            $begingroup$


            Wolfram Language (Mathematica), 51 bytes



            Union@NestList[#+10^Floor@Log10@Min[s-#,#]&,1,s=#]&


            Try it online!






            share|improve this answer









            $endgroup$





















              1












              $begingroup$

              Batch, 131 bytes



              @set/an=i=1
              :e
              @if %n%==%i%0 set i=%i%0
              @echo %n%
              :c
              @set/an+=i
              @if %n% leq %1 goto e
              @set/an-=i,i/=10
              @if %i% neq 0 goto c


              Takes input as a command-line parameter and outputs the list of numbers to STDOUT. Explanation:



              @set/an=i=1


              Start with n=1 and i=1 representing the power of 10.



              :e
              @if %n%==%i%0 set i=%i%0


              Multiply i by 10 if n has reached the next power of 10.



              @echo %n%


              Output the current value of n.



              :c
              @set/an+=i
              @if %n% leq %1 goto e


              Repeat while i can be added to n without it exceeding the input.



              @set/an-=i,i/=10


              Restore the previous value of n and divide i by 10.



              @if %i% neq 0 goto c


              If i is not zero then try adding i to n again.






              share|improve this answer









              $endgroup$





















                1












                $begingroup$


                R, 67 65 bytes



                -2 bytes thanks to Giuseppe



                k=scan();o=1;i=10^(k:0);while(T<k)o=c(o,T<-T+i[i<=T&i+T<=k][1]);o


                Pretty simple. It takes a set of powers of 10 beyond what would be needed in reverse order i.



                (I would prefer to use i=10^rev(0:log10(k)) instead of i=10^(k:0) since the latter is computationally ineffecient, but golf is golf!).



                Then in a while loop, applies the conditions to i and takes the first (i.e. largest); updates n, and appends to output



                Try it online!






                share|improve this answer











                $endgroup$









                • 1




                  $begingroup$
                  Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                  $endgroup$
                  – Giuseppe
                  Apr 3 at 13:15






                • 1




                  $begingroup$
                  That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                  $endgroup$
                  – Aaron Hayman
                  Apr 3 at 13:23



















                1












                $begingroup$


                Jelly, 12 bytes



                1+«ạæḟ⁵«Ɗɗ¥Ƭ


                Try it online!






                share|improve this answer









                $endgroup$





















                  1












                  $begingroup$


                  Pip, 27 bytes



                  Wa>Po+:y/t*Y1Ty>o|o+y>ay*:t


                  Try it online!



                  In pseudocode:



                  a = args[0]
                  o = 1
                  print o
                  while a > o {
                  y = 1
                  till y > o || o + y > a
                  y *= 10
                  o += y / 10
                  print o
                  }


                  I'm pretty pleased with the golfing tricks I was able to apply to shorten this algorithm. By initializing, updating, and printing stuff in the loop header, I was able to avoid needing curly braces for the loop body. There's probably a golfier algorithm, though.






                  share|improve this answer









                  $endgroup$





















                    0












                    $begingroup$


                    Japt, 18 bytes



                    ÆT±ApTmTnU)sÊÉÃf§U


                    Try it



                    ÆT±ApTmTnU)sÊÉÃf§U     :Implicit input of integer U
                    Æ :Map the range [0,U)
                    T± : Increment T (initially 0) by
                    A : 10
                    p : Raised to the power of
                    Tm : The minimum of T and
                    TnU : T subtracted from U
                    ) : End minimum
                    s : Convert to string
                    Ê : Length
                    É : Subtract 1
                    Ã :End map
                    f :Filter
                    §U : Less than or equal to U





                    share|improve this answer









                    $endgroup$





















                      0












                      $begingroup$


                      C# (Visual C# Interactive Compiler), 123 122 bytes





                      m=>{var a=new{1}.ToList();int s;for(;(s=a.Last())<m;)a.Add(s+(int)Math.Pow(10,(int)Math.Log(s<m-s?s:m-s,10)));return a;}


                      Try it online!






                      share|improve this answer











                      $endgroup$





















                        0












                        $begingroup$


                        Prolog (SWI), 142 bytes



                        L-D-M:-append(L,[D],M).
                        N-L-C-X-R-I:-I=1,C is X*10,N-L-C-C-R-1;D is C+X,(D<N,L-D-M,N-M-D-X-R-I;D>N,N-L-C-(X/10)-R-0;L-D-R).
                        N-R:-N--0-1-R-1.


                        Try it online!



                        Explanation coming tomorrow or something






                        share|improve this answer









                        $endgroup$














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                          15 Answers
                          15






                          active

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                          15 Answers
                          15






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                          active

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                          oldest

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                          7












                          $begingroup$


                          Haskell, 72 68 64 63 bytes





                          f=(1!)
                          c!t|t==c=[c]|t>c=c:(c+10^(pred.length.show.min c$t-c))!t


                          Try it online!



                          Thanks Sriotchilism O'Zaic for -4 bytes!



                          Usage



                          f 321
                          [1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100,200,300,310,320,321]


                          Explanation



                          c!t         -- c=current number, t=target number
                          |t==c=[c] -- Target is reached, return last number
                          |t>c=c:(c+10^(pred.length.show.min c$t-c))!t
                          c: -- Add current number to list
                          min c$t-c -- The minimum of the current number, and the difference between the current number and the target
                          length.show. -- The length of this number
                          pred. -- Minus 1
                          10^( ) -- Raise 10 to this power
                          c+ -- Add that to the current number
                          ( )!t -- Recursion





                          share|improve this answer










                          New contributor




                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.






                          $endgroup$









                          • 4




                            $begingroup$
                            Welcome to PPCG! Nice first answer.
                            $endgroup$
                            – Arnauld
                            Apr 3 at 9:13






                          • 2




                            $begingroup$
                            I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
                            $endgroup$
                            – Kevin Cruijssen
                            Apr 3 at 9:21








                          • 2




                            $begingroup$
                            Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
                            $endgroup$
                            – Sriotchilism O'Zaic
                            Apr 3 at 13:24








                          • 1




                            $begingroup$
                            pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:27






                          • 1




                            $begingroup$
                            Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:37
















                          7












                          $begingroup$


                          Haskell, 72 68 64 63 bytes





                          f=(1!)
                          c!t|t==c=[c]|t>c=c:(c+10^(pred.length.show.min c$t-c))!t


                          Try it online!



                          Thanks Sriotchilism O'Zaic for -4 bytes!



                          Usage



                          f 321
                          [1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100,200,300,310,320,321]


                          Explanation



                          c!t         -- c=current number, t=target number
                          |t==c=[c] -- Target is reached, return last number
                          |t>c=c:(c+10^(pred.length.show.min c$t-c))!t
                          c: -- Add current number to list
                          min c$t-c -- The minimum of the current number, and the difference between the current number and the target
                          length.show. -- The length of this number
                          pred. -- Minus 1
                          10^( ) -- Raise 10 to this power
                          c+ -- Add that to the current number
                          ( )!t -- Recursion





                          share|improve this answer










                          New contributor




                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.






                          $endgroup$









                          • 4




                            $begingroup$
                            Welcome to PPCG! Nice first answer.
                            $endgroup$
                            – Arnauld
                            Apr 3 at 9:13






                          • 2




                            $begingroup$
                            I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
                            $endgroup$
                            – Kevin Cruijssen
                            Apr 3 at 9:21








                          • 2




                            $begingroup$
                            Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
                            $endgroup$
                            – Sriotchilism O'Zaic
                            Apr 3 at 13:24








                          • 1




                            $begingroup$
                            pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:27






                          • 1




                            $begingroup$
                            Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:37














                          7












                          7








                          7





                          $begingroup$


                          Haskell, 72 68 64 63 bytes





                          f=(1!)
                          c!t|t==c=[c]|t>c=c:(c+10^(pred.length.show.min c$t-c))!t


                          Try it online!



                          Thanks Sriotchilism O'Zaic for -4 bytes!



                          Usage



                          f 321
                          [1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100,200,300,310,320,321]


                          Explanation



                          c!t         -- c=current number, t=target number
                          |t==c=[c] -- Target is reached, return last number
                          |t>c=c:(c+10^(pred.length.show.min c$t-c))!t
                          c: -- Add current number to list
                          min c$t-c -- The minimum of the current number, and the difference between the current number and the target
                          length.show. -- The length of this number
                          pred. -- Minus 1
                          10^( ) -- Raise 10 to this power
                          c+ -- Add that to the current number
                          ( )!t -- Recursion





                          share|improve this answer










                          New contributor




                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.






                          $endgroup$




                          Haskell, 72 68 64 63 bytes





                          f=(1!)
                          c!t|t==c=[c]|t>c=c:(c+10^(pred.length.show.min c$t-c))!t


                          Try it online!



                          Thanks Sriotchilism O'Zaic for -4 bytes!



                          Usage



                          f 321
                          [1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100,200,300,310,320,321]


                          Explanation



                          c!t         -- c=current number, t=target number
                          |t==c=[c] -- Target is reached, return last number
                          |t>c=c:(c+10^(pred.length.show.min c$t-c))!t
                          c: -- Add current number to list
                          min c$t-c -- The minimum of the current number, and the difference between the current number and the target
                          length.show. -- The length of this number
                          pred. -- Minus 1
                          10^( ) -- Raise 10 to this power
                          c+ -- Add that to the current number
                          ( )!t -- Recursion






                          share|improve this answer










                          New contributor




                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.









                          share|improve this answer



                          share|improve this answer








                          edited Apr 4 at 7:17





















                          New contributor




                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.









                          answered Apr 3 at 9:12









                          Paul MutserPaul Mutser

                          712




                          712




                          New contributor




                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.





                          New contributor





                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.






                          Paul Mutser is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
                          Check out our Code of Conduct.








                          • 4




                            $begingroup$
                            Welcome to PPCG! Nice first answer.
                            $endgroup$
                            – Arnauld
                            Apr 3 at 9:13






                          • 2




                            $begingroup$
                            I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
                            $endgroup$
                            – Kevin Cruijssen
                            Apr 3 at 9:21








                          • 2




                            $begingroup$
                            Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
                            $endgroup$
                            – Sriotchilism O'Zaic
                            Apr 3 at 13:24








                          • 1




                            $begingroup$
                            pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:27






                          • 1




                            $begingroup$
                            Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:37














                          • 4




                            $begingroup$
                            Welcome to PPCG! Nice first answer.
                            $endgroup$
                            – Arnauld
                            Apr 3 at 9:13






                          • 2




                            $begingroup$
                            I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
                            $endgroup$
                            – Kevin Cruijssen
                            Apr 3 at 9:21








                          • 2




                            $begingroup$
                            Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
                            $endgroup$
                            – Sriotchilism O'Zaic
                            Apr 3 at 13:24








                          • 1




                            $begingroup$
                            pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:27






                          • 1




                            $begingroup$
                            Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
                            $endgroup$
                            – Laikoni
                            Apr 4 at 9:37








                          4




                          4




                          $begingroup$
                          Welcome to PPCG! Nice first answer.
                          $endgroup$
                          – Arnauld
                          Apr 3 at 9:13




                          $begingroup$
                          Welcome to PPCG! Nice first answer.
                          $endgroup$
                          – Arnauld
                          Apr 3 at 9:13




                          2




                          2




                          $begingroup$
                          I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
                          $endgroup$
                          – Kevin Cruijssen
                          Apr 3 at 9:21






                          $begingroup$
                          I don't know Haskell, but maybe any of these tips might help: tips for golfing in Haskell and tips for golfing in <all languages>. But I agree, nice answer. +1 from me.
                          $endgroup$
                          – Kevin Cruijssen
                          Apr 3 at 9:21






                          2




                          2




                          $begingroup$
                          Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
                          $endgroup$
                          – Sriotchilism O'Zaic
                          Apr 3 at 13:24






                          $begingroup$
                          Welcome to the site! Since (^) is higher precedence than (+) you don't need parentheses around the (^) expression. Same goes for (!) and (:)
                          $endgroup$
                          – Sriotchilism O'Zaic
                          Apr 3 at 13:24






                          1




                          1




                          $begingroup$
                          pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
                          $endgroup$
                          – Laikoni
                          Apr 4 at 9:27




                          $begingroup$
                          pred.length.show.min c$t-c can be shortened to length(show.min c$t-c)-1. Anonymous functions are acceptable, so you can drop the leading f= as explained in our guide to golfing rules in Haskell.
                          $endgroup$
                          – Laikoni
                          Apr 4 at 9:27




                          1




                          1




                          $begingroup$
                          Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
                          $endgroup$
                          – Laikoni
                          Apr 4 at 9:37




                          $begingroup$
                          Instead of guards, you can use only one case and a conditional: c!t=c: if t>c then (c+10^(length(show.min c$t-c)-1))!t else . This allows to apply this tip to save a few more bytes: Try it online!
                          $endgroup$
                          – Laikoni
                          Apr 4 at 9:37











                          6












                          $begingroup$

                          JavaScript (ES6), 50 bytes



                          f=n=>n?[...f(n-(1+/(^10)?(0*$)/.exec(n)[2])),n]:


                          Try it online!



                          How?



                          Theory



                          The following steps are repeated until $n=0$:




                          • look for the number $k$ of trailing zeros in the decimal representation of $n$

                          • decrement $k$ if $n$ is an exact power of $10$

                          • subtract $x=10^k$ from $n$


                          Implementation



                          The value of $x$ is directly computed as a string with the following expression:



                          +---- leading '1'
                          |
                          1 + /(^10)?(0*$)/.exec(n)[2]
                          ____/___/
                          | |
                          | +---- trailing zeros (the capturing group that is appended to the leading '1')
                          +--------- discard one zero if n starts with '10'


                          Note: Excluding the leading '10' only affects exact powers of $10$ (e.g. $n=color{red}{10}color{green}{00}$) but does not change the number of captured trailing zeros for values such as $n=color{red}{10}23color{green}{00}$ (because of the extra non-zero middle digits, '10' is actually not matched at all in such cases).






                          share|improve this answer











                          $endgroup$













                          • $begingroup$
                            Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
                            $endgroup$
                            – Ørjan Johansen
                            Apr 4 at 17:36


















                          6












                          $begingroup$

                          JavaScript (ES6), 50 bytes



                          f=n=>n?[...f(n-(1+/(^10)?(0*$)/.exec(n)[2])),n]:


                          Try it online!



                          How?



                          Theory



                          The following steps are repeated until $n=0$:




                          • look for the number $k$ of trailing zeros in the decimal representation of $n$

                          • decrement $k$ if $n$ is an exact power of $10$

                          • subtract $x=10^k$ from $n$


                          Implementation



                          The value of $x$ is directly computed as a string with the following expression:



                          +---- leading '1'
                          |
                          1 + /(^10)?(0*$)/.exec(n)[2]
                          ____/___/
                          | |
                          | +---- trailing zeros (the capturing group that is appended to the leading '1')
                          +--------- discard one zero if n starts with '10'


                          Note: Excluding the leading '10' only affects exact powers of $10$ (e.g. $n=color{red}{10}color{green}{00}$) but does not change the number of captured trailing zeros for values such as $n=color{red}{10}23color{green}{00}$ (because of the extra non-zero middle digits, '10' is actually not matched at all in such cases).






                          share|improve this answer











                          $endgroup$













                          • $begingroup$
                            Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
                            $endgroup$
                            – Ørjan Johansen
                            Apr 4 at 17:36
















                          6












                          6








                          6





                          $begingroup$

                          JavaScript (ES6), 50 bytes



                          f=n=>n?[...f(n-(1+/(^10)?(0*$)/.exec(n)[2])),n]:


                          Try it online!



                          How?



                          Theory



                          The following steps are repeated until $n=0$:




                          • look for the number $k$ of trailing zeros in the decimal representation of $n$

                          • decrement $k$ if $n$ is an exact power of $10$

                          • subtract $x=10^k$ from $n$


                          Implementation



                          The value of $x$ is directly computed as a string with the following expression:



                          +---- leading '1'
                          |
                          1 + /(^10)?(0*$)/.exec(n)[2]
                          ____/___/
                          | |
                          | +---- trailing zeros (the capturing group that is appended to the leading '1')
                          +--------- discard one zero if n starts with '10'


                          Note: Excluding the leading '10' only affects exact powers of $10$ (e.g. $n=color{red}{10}color{green}{00}$) but does not change the number of captured trailing zeros for values such as $n=color{red}{10}23color{green}{00}$ (because of the extra non-zero middle digits, '10' is actually not matched at all in such cases).






                          share|improve this answer











                          $endgroup$



                          JavaScript (ES6), 50 bytes



                          f=n=>n?[...f(n-(1+/(^10)?(0*$)/.exec(n)[2])),n]:


                          Try it online!



                          How?



                          Theory



                          The following steps are repeated until $n=0$:




                          • look for the number $k$ of trailing zeros in the decimal representation of $n$

                          • decrement $k$ if $n$ is an exact power of $10$

                          • subtract $x=10^k$ from $n$


                          Implementation



                          The value of $x$ is directly computed as a string with the following expression:



                          +---- leading '1'
                          |
                          1 + /(^10)?(0*$)/.exec(n)[2]
                          ____/___/
                          | |
                          | +---- trailing zeros (the capturing group that is appended to the leading '1')
                          +--------- discard one zero if n starts with '10'


                          Note: Excluding the leading '10' only affects exact powers of $10$ (e.g. $n=color{red}{10}color{green}{00}$) but does not change the number of captured trailing zeros for values such as $n=color{red}{10}23color{green}{00}$ (because of the extra non-zero middle digits, '10' is actually not matched at all in such cases).







                          share|improve this answer














                          share|improve this answer



                          share|improve this answer








                          edited Apr 3 at 8:35

























                          answered Apr 3 at 7:36









                          ArnauldArnauld

                          80.7k797334




                          80.7k797334












                          • $begingroup$
                            Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
                            $endgroup$
                            – Ørjan Johansen
                            Apr 4 at 17:36




















                          • $begingroup$
                            Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
                            $endgroup$
                            – Ørjan Johansen
                            Apr 4 at 17:36


















                          $begingroup$
                          Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
                          $endgroup$
                          – Ørjan Johansen
                          Apr 4 at 17:36






                          $begingroup$
                          Ingenious noting you can do the iteration "backwards" keeping track of only one variable! It's a bit confusing that you use k for something completely different than in the challenge description (in fact your n is a mix of OP's n and k and your x is their i.)
                          $endgroup$
                          – Ørjan Johansen
                          Apr 4 at 17:36













                          3












                          $begingroup$


                          Python 2, 61 bytes





                          f=lambda k,n=1:n<k and[n]+f(k,n+10**~-len(`min(n,k-n)`))or[n]


                          Try it online!






                          share|improve this answer











                          $endgroup$


















                            3












                            $begingroup$


                            Python 2, 61 bytes





                            f=lambda k,n=1:n<k and[n]+f(k,n+10**~-len(`min(n,k-n)`))or[n]


                            Try it online!






                            share|improve this answer











                            $endgroup$
















                              3












                              3








                              3





                              $begingroup$


                              Python 2, 61 bytes





                              f=lambda k,n=1:n<k and[n]+f(k,n+10**~-len(`min(n,k-n)`))or[n]


                              Try it online!






                              share|improve this answer











                              $endgroup$




                              Python 2, 61 bytes





                              f=lambda k,n=1:n<k and[n]+f(k,n+10**~-len(`min(n,k-n)`))or[n]


                              Try it online!







                              share|improve this answer














                              share|improve this answer



                              share|improve this answer








                              edited Apr 3 at 6:08

























                              answered Apr 3 at 6:02









                              Chas BrownChas Brown

                              5,2191523




                              5,2191523























                                  2












                                  $begingroup$


                                  Perl 6, 48 41 bytes





                                  ->k{1,{$_+10**min($_,k-$_).comb/10}...k}


                                  Try it online!



                                  Explanation:



                                  ->k{                                   }  # Anonymous code block taking k
                                  1, ...k # Start a sequence from 1 to k
                                  { } # Where each element is
                                  $_+ # The previous element plus
                                  10** # 10 to the power of
                                  .comb # The length of
                                  min($_,k-$_) # The min of the current count and the remainder
                                  /10 # Minus one





                                  share|improve this answer











                                  $endgroup$


















                                    2












                                    $begingroup$


                                    Perl 6, 48 41 bytes





                                    ->k{1,{$_+10**min($_,k-$_).comb/10}...k}


                                    Try it online!



                                    Explanation:



                                    ->k{                                   }  # Anonymous code block taking k
                                    1, ...k # Start a sequence from 1 to k
                                    { } # Where each element is
                                    $_+ # The previous element plus
                                    10** # 10 to the power of
                                    .comb # The length of
                                    min($_,k-$_) # The min of the current count and the remainder
                                    /10 # Minus one





                                    share|improve this answer











                                    $endgroup$
















                                      2












                                      2








                                      2





                                      $begingroup$


                                      Perl 6, 48 41 bytes





                                      ->k{1,{$_+10**min($_,k-$_).comb/10}...k}


                                      Try it online!



                                      Explanation:



                                      ->k{                                   }  # Anonymous code block taking k
                                      1, ...k # Start a sequence from 1 to k
                                      { } # Where each element is
                                      $_+ # The previous element plus
                                      10** # 10 to the power of
                                      .comb # The length of
                                      min($_,k-$_) # The min of the current count and the remainder
                                      /10 # Minus one





                                      share|improve this answer











                                      $endgroup$




                                      Perl 6, 48 41 bytes





                                      ->k{1,{$_+10**min($_,k-$_).comb/10}...k}


                                      Try it online!



                                      Explanation:



                                      ->k{                                   }  # Anonymous code block taking k
                                      1, ...k # Start a sequence from 1 to k
                                      { } # Where each element is
                                      $_+ # The previous element plus
                                      10** # 10 to the power of
                                      .comb # The length of
                                      min($_,k-$_) # The min of the current count and the remainder
                                      /10 # Minus one






                                      share|improve this answer














                                      share|improve this answer



                                      share|improve this answer








                                      edited Apr 3 at 6:13

























                                      answered Apr 3 at 5:50









                                      Jo KingJo King

                                      26.6k365132




                                      26.6k365132























                                          2












                                          $begingroup$


                                          APL (Dyalog Unicode), 30 bytesSBCS





                                          Anonymous tacit prefix function. Prints numbers on separate lines to stdout.



                                          {⍺=⍵:⍺⋄⍺∇⍵+10*⌊/⌊10⍟⍵,⍺-⎕←⍵}∘1


                                          Try it online!



                                          {}∘1 anonymous infix lambda with 1 curried as initial $n$:



                                          ⍺=⍵ if $k$ and $n$ are equal:



                                             return (and implicitly print) $k$



                                            else:



                                            ⎕←⍵ print $n$



                                            ⍺- subtract that from $k$



                                            ⍵, prepend $n$



                                            10⍟$log_{10}$ of those



                                             floor those



                                            ⌊/ minimum of those



                                            10* ten raised to the power of that



                                            ⍵+$n$ plus that



                                            ⍺∇ recurse using same $k$ and new $n$








                                          share|improve this answer









                                          $endgroup$


















                                            2












                                            $begingroup$


                                            APL (Dyalog Unicode), 30 bytesSBCS





                                            Anonymous tacit prefix function. Prints numbers on separate lines to stdout.



                                            {⍺=⍵:⍺⋄⍺∇⍵+10*⌊/⌊10⍟⍵,⍺-⎕←⍵}∘1


                                            Try it online!



                                            {}∘1 anonymous infix lambda with 1 curried as initial $n$:



                                            ⍺=⍵ if $k$ and $n$ are equal:



                                               return (and implicitly print) $k$



                                              else:



                                              ⎕←⍵ print $n$



                                              ⍺- subtract that from $k$



                                              ⍵, prepend $n$



                                              10⍟$log_{10}$ of those



                                               floor those



                                              ⌊/ minimum of those



                                              10* ten raised to the power of that



                                              ⍵+$n$ plus that



                                              ⍺∇ recurse using same $k$ and new $n$








                                            share|improve this answer









                                            $endgroup$
















                                              2












                                              2








                                              2





                                              $begingroup$


                                              APL (Dyalog Unicode), 30 bytesSBCS





                                              Anonymous tacit prefix function. Prints numbers on separate lines to stdout.



                                              {⍺=⍵:⍺⋄⍺∇⍵+10*⌊/⌊10⍟⍵,⍺-⎕←⍵}∘1


                                              Try it online!



                                              {}∘1 anonymous infix lambda with 1 curried as initial $n$:



                                              ⍺=⍵ if $k$ and $n$ are equal:



                                                 return (and implicitly print) $k$



                                                else:



                                                ⎕←⍵ print $n$



                                                ⍺- subtract that from $k$



                                                ⍵, prepend $n$



                                                10⍟$log_{10}$ of those



                                                 floor those



                                                ⌊/ minimum of those



                                                10* ten raised to the power of that



                                                ⍵+$n$ plus that



                                                ⍺∇ recurse using same $k$ and new $n$








                                              share|improve this answer









                                              $endgroup$




                                              APL (Dyalog Unicode), 30 bytesSBCS





                                              Anonymous tacit prefix function. Prints numbers on separate lines to stdout.



                                              {⍺=⍵:⍺⋄⍺∇⍵+10*⌊/⌊10⍟⍵,⍺-⎕←⍵}∘1


                                              Try it online!



                                              {}∘1 anonymous infix lambda with 1 curried as initial $n$:



                                              ⍺=⍵ if $k$ and $n$ are equal:



                                                 return (and implicitly print) $k$



                                                else:



                                                ⎕←⍵ print $n$



                                                ⍺- subtract that from $k$



                                                ⍵, prepend $n$



                                                10⍟$log_{10}$ of those



                                                 floor those



                                                ⌊/ minimum of those



                                                10* ten raised to the power of that



                                                ⍵+$n$ plus that



                                                ⍺∇ recurse using same $k$ and new $n$









                                              share|improve this answer












                                              share|improve this answer



                                              share|improve this answer










                                              answered Apr 3 at 8:21









                                              AdámAdám

                                              29k276207




                                              29k276207























                                                  2












                                                  $begingroup$


                                                  05AB1E, 15 bytes



                                                  1[=ÐIαD_#‚ßg<°+


                                                  Port of @PaulMutser's (first) Haskell answer, so make sure to upvote him!!



                                                  Try it online or verify all test cases.



                                                  Outputs the numbers newline delimited.

                                                  If it must be a list, I'd have to add 3 bytes:



                                                  X[DˆÐIαD_#‚ßg<°+}¯


                                                  Try it online or verify all test cases.



                                                  Explanation:





                                                  1             # Push a 1 to the stack
                                                  [ # Start an infinite loop
                                                  = # Print the current number with trailing newline (without popping it)
                                                  Ð # Triplicate the current number
                                                  Iα # Get the absolute difference with the input
                                                  D # Duplicate that absolute difference
                                                  _ # If this difference is 0:
                                                  # # Stop the infinite loop
                                                  ‚ß # Pair it with the current number, and pop and push the minimum
                                                  g<° # Calculate 10 to the power of the length of the minimum minus 1
                                                  + # And add it to the current number





                                                  share|improve this answer











                                                  $endgroup$


















                                                    2












                                                    $begingroup$


                                                    05AB1E, 15 bytes



                                                    1[=ÐIαD_#‚ßg<°+


                                                    Port of @PaulMutser's (first) Haskell answer, so make sure to upvote him!!



                                                    Try it online or verify all test cases.



                                                    Outputs the numbers newline delimited.

                                                    If it must be a list, I'd have to add 3 bytes:



                                                    X[DˆÐIαD_#‚ßg<°+}¯


                                                    Try it online or verify all test cases.



                                                    Explanation:





                                                    1             # Push a 1 to the stack
                                                    [ # Start an infinite loop
                                                    = # Print the current number with trailing newline (without popping it)
                                                    Ð # Triplicate the current number
                                                    Iα # Get the absolute difference with the input
                                                    D # Duplicate that absolute difference
                                                    _ # If this difference is 0:
                                                    # # Stop the infinite loop
                                                    ‚ß # Pair it with the current number, and pop and push the minimum
                                                    g<° # Calculate 10 to the power of the length of the minimum minus 1
                                                    + # And add it to the current number





                                                    share|improve this answer











                                                    $endgroup$
















                                                      2












                                                      2








                                                      2





                                                      $begingroup$


                                                      05AB1E, 15 bytes



                                                      1[=ÐIαD_#‚ßg<°+


                                                      Port of @PaulMutser's (first) Haskell answer, so make sure to upvote him!!



                                                      Try it online or verify all test cases.



                                                      Outputs the numbers newline delimited.

                                                      If it must be a list, I'd have to add 3 bytes:



                                                      X[DˆÐIαD_#‚ßg<°+}¯


                                                      Try it online or verify all test cases.



                                                      Explanation:





                                                      1             # Push a 1 to the stack
                                                      [ # Start an infinite loop
                                                      = # Print the current number with trailing newline (without popping it)
                                                      Ð # Triplicate the current number
                                                      Iα # Get the absolute difference with the input
                                                      D # Duplicate that absolute difference
                                                      _ # If this difference is 0:
                                                      # # Stop the infinite loop
                                                      ‚ß # Pair it with the current number, and pop and push the minimum
                                                      g<° # Calculate 10 to the power of the length of the minimum minus 1
                                                      + # And add it to the current number





                                                      share|improve this answer











                                                      $endgroup$




                                                      05AB1E, 15 bytes



                                                      1[=ÐIαD_#‚ßg<°+


                                                      Port of @PaulMutser's (first) Haskell answer, so make sure to upvote him!!



                                                      Try it online or verify all test cases.



                                                      Outputs the numbers newline delimited.

                                                      If it must be a list, I'd have to add 3 bytes:



                                                      X[DˆÐIαD_#‚ßg<°+}¯


                                                      Try it online or verify all test cases.



                                                      Explanation:





                                                      1             # Push a 1 to the stack
                                                      [ # Start an infinite loop
                                                      = # Print the current number with trailing newline (without popping it)
                                                      Ð # Triplicate the current number
                                                      Iα # Get the absolute difference with the input
                                                      D # Duplicate that absolute difference
                                                      _ # If this difference is 0:
                                                      # # Stop the infinite loop
                                                      ‚ß # Pair it with the current number, and pop and push the minimum
                                                      g<° # Calculate 10 to the power of the length of the minimum minus 1
                                                      + # And add it to the current number






                                                      share|improve this answer














                                                      share|improve this answer



                                                      share|improve this answer








                                                      edited Apr 3 at 9:51

























                                                      answered Apr 3 at 9:43









                                                      Kevin CruijssenKevin Cruijssen

                                                      42.6k571217




                                                      42.6k571217























                                                          1












                                                          $begingroup$


                                                          Jelly, 19 bytes



                                                          1µ«³_$DL’⁵*$+µ<³$п


                                                          Try it online!






                                                          share|improve this answer









                                                          $endgroup$


















                                                            1












                                                            $begingroup$


                                                            Jelly, 19 bytes



                                                            1µ«³_$DL’⁵*$+µ<³$п


                                                            Try it online!






                                                            share|improve this answer









                                                            $endgroup$
















                                                              1












                                                              1








                                                              1





                                                              $begingroup$


                                                              Jelly, 19 bytes



                                                              1µ«³_$DL’⁵*$+µ<³$п


                                                              Try it online!






                                                              share|improve this answer









                                                              $endgroup$




                                                              Jelly, 19 bytes



                                                              1µ«³_$DL’⁵*$+µ<³$п


                                                              Try it online!







                                                              share|improve this answer












                                                              share|improve this answer



                                                              share|improve this answer










                                                              answered Apr 3 at 7:41









                                                              Nick KennedyNick Kennedy

                                                              1,46649




                                                              1,46649























                                                                  1












                                                                  $begingroup$


                                                                  Wolfram Language (Mathematica), 51 bytes



                                                                  Union@NestList[#+10^Floor@Log10@Min[s-#,#]&,1,s=#]&


                                                                  Try it online!






                                                                  share|improve this answer









                                                                  $endgroup$


















                                                                    1












                                                                    $begingroup$


                                                                    Wolfram Language (Mathematica), 51 bytes



                                                                    Union@NestList[#+10^Floor@Log10@Min[s-#,#]&,1,s=#]&


                                                                    Try it online!






                                                                    share|improve this answer









                                                                    $endgroup$
















                                                                      1












                                                                      1








                                                                      1





                                                                      $begingroup$


                                                                      Wolfram Language (Mathematica), 51 bytes



                                                                      Union@NestList[#+10^Floor@Log10@Min[s-#,#]&,1,s=#]&


                                                                      Try it online!






                                                                      share|improve this answer









                                                                      $endgroup$




                                                                      Wolfram Language (Mathematica), 51 bytes



                                                                      Union@NestList[#+10^Floor@Log10@Min[s-#,#]&,1,s=#]&


                                                                      Try it online!







                                                                      share|improve this answer












                                                                      share|improve this answer



                                                                      share|improve this answer










                                                                      answered Apr 3 at 8:15









                                                                      J42161217J42161217

                                                                      13.9k21353




                                                                      13.9k21353























                                                                          1












                                                                          $begingroup$

                                                                          Batch, 131 bytes



                                                                          @set/an=i=1
                                                                          :e
                                                                          @if %n%==%i%0 set i=%i%0
                                                                          @echo %n%
                                                                          :c
                                                                          @set/an+=i
                                                                          @if %n% leq %1 goto e
                                                                          @set/an-=i,i/=10
                                                                          @if %i% neq 0 goto c


                                                                          Takes input as a command-line parameter and outputs the list of numbers to STDOUT. Explanation:



                                                                          @set/an=i=1


                                                                          Start with n=1 and i=1 representing the power of 10.



                                                                          :e
                                                                          @if %n%==%i%0 set i=%i%0


                                                                          Multiply i by 10 if n has reached the next power of 10.



                                                                          @echo %n%


                                                                          Output the current value of n.



                                                                          :c
                                                                          @set/an+=i
                                                                          @if %n% leq %1 goto e


                                                                          Repeat while i can be added to n without it exceeding the input.



                                                                          @set/an-=i,i/=10


                                                                          Restore the previous value of n and divide i by 10.



                                                                          @if %i% neq 0 goto c


                                                                          If i is not zero then try adding i to n again.






                                                                          share|improve this answer









                                                                          $endgroup$


















                                                                            1












                                                                            $begingroup$

                                                                            Batch, 131 bytes



                                                                            @set/an=i=1
                                                                            :e
                                                                            @if %n%==%i%0 set i=%i%0
                                                                            @echo %n%
                                                                            :c
                                                                            @set/an+=i
                                                                            @if %n% leq %1 goto e
                                                                            @set/an-=i,i/=10
                                                                            @if %i% neq 0 goto c


                                                                            Takes input as a command-line parameter and outputs the list of numbers to STDOUT. Explanation:



                                                                            @set/an=i=1


                                                                            Start with n=1 and i=1 representing the power of 10.



                                                                            :e
                                                                            @if %n%==%i%0 set i=%i%0


                                                                            Multiply i by 10 if n has reached the next power of 10.



                                                                            @echo %n%


                                                                            Output the current value of n.



                                                                            :c
                                                                            @set/an+=i
                                                                            @if %n% leq %1 goto e


                                                                            Repeat while i can be added to n without it exceeding the input.



                                                                            @set/an-=i,i/=10


                                                                            Restore the previous value of n and divide i by 10.



                                                                            @if %i% neq 0 goto c


                                                                            If i is not zero then try adding i to n again.






                                                                            share|improve this answer









                                                                            $endgroup$
















                                                                              1












                                                                              1








                                                                              1





                                                                              $begingroup$

                                                                              Batch, 131 bytes



                                                                              @set/an=i=1
                                                                              :e
                                                                              @if %n%==%i%0 set i=%i%0
                                                                              @echo %n%
                                                                              :c
                                                                              @set/an+=i
                                                                              @if %n% leq %1 goto e
                                                                              @set/an-=i,i/=10
                                                                              @if %i% neq 0 goto c


                                                                              Takes input as a command-line parameter and outputs the list of numbers to STDOUT. Explanation:



                                                                              @set/an=i=1


                                                                              Start with n=1 and i=1 representing the power of 10.



                                                                              :e
                                                                              @if %n%==%i%0 set i=%i%0


                                                                              Multiply i by 10 if n has reached the next power of 10.



                                                                              @echo %n%


                                                                              Output the current value of n.



                                                                              :c
                                                                              @set/an+=i
                                                                              @if %n% leq %1 goto e


                                                                              Repeat while i can be added to n without it exceeding the input.



                                                                              @set/an-=i,i/=10


                                                                              Restore the previous value of n and divide i by 10.



                                                                              @if %i% neq 0 goto c


                                                                              If i is not zero then try adding i to n again.






                                                                              share|improve this answer









                                                                              $endgroup$



                                                                              Batch, 131 bytes



                                                                              @set/an=i=1
                                                                              :e
                                                                              @if %n%==%i%0 set i=%i%0
                                                                              @echo %n%
                                                                              :c
                                                                              @set/an+=i
                                                                              @if %n% leq %1 goto e
                                                                              @set/an-=i,i/=10
                                                                              @if %i% neq 0 goto c


                                                                              Takes input as a command-line parameter and outputs the list of numbers to STDOUT. Explanation:



                                                                              @set/an=i=1


                                                                              Start with n=1 and i=1 representing the power of 10.



                                                                              :e
                                                                              @if %n%==%i%0 set i=%i%0


                                                                              Multiply i by 10 if n has reached the next power of 10.



                                                                              @echo %n%


                                                                              Output the current value of n.



                                                                              :c
                                                                              @set/an+=i
                                                                              @if %n% leq %1 goto e


                                                                              Repeat while i can be added to n without it exceeding the input.



                                                                              @set/an-=i,i/=10


                                                                              Restore the previous value of n and divide i by 10.



                                                                              @if %i% neq 0 goto c


                                                                              If i is not zero then try adding i to n again.







                                                                              share|improve this answer












                                                                              share|improve this answer



                                                                              share|improve this answer










                                                                              answered Apr 3 at 9:25









                                                                              NeilNeil

                                                                              82.7k745179




                                                                              82.7k745179























                                                                                  1












                                                                                  $begingroup$


                                                                                  R, 67 65 bytes



                                                                                  -2 bytes thanks to Giuseppe



                                                                                  k=scan();o=1;i=10^(k:0);while(T<k)o=c(o,T<-T+i[i<=T&i+T<=k][1]);o


                                                                                  Pretty simple. It takes a set of powers of 10 beyond what would be needed in reverse order i.



                                                                                  (I would prefer to use i=10^rev(0:log10(k)) instead of i=10^(k:0) since the latter is computationally ineffecient, but golf is golf!).



                                                                                  Then in a while loop, applies the conditions to i and takes the first (i.e. largest); updates n, and appends to output



                                                                                  Try it online!






                                                                                  share|improve this answer











                                                                                  $endgroup$









                                                                                  • 1




                                                                                    $begingroup$
                                                                                    Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                                                                                    $endgroup$
                                                                                    – Giuseppe
                                                                                    Apr 3 at 13:15






                                                                                  • 1




                                                                                    $begingroup$
                                                                                    That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                                                                                    $endgroup$
                                                                                    – Aaron Hayman
                                                                                    Apr 3 at 13:23
















                                                                                  1












                                                                                  $begingroup$


                                                                                  R, 67 65 bytes



                                                                                  -2 bytes thanks to Giuseppe



                                                                                  k=scan();o=1;i=10^(k:0);while(T<k)o=c(o,T<-T+i[i<=T&i+T<=k][1]);o


                                                                                  Pretty simple. It takes a set of powers of 10 beyond what would be needed in reverse order i.



                                                                                  (I would prefer to use i=10^rev(0:log10(k)) instead of i=10^(k:0) since the latter is computationally ineffecient, but golf is golf!).



                                                                                  Then in a while loop, applies the conditions to i and takes the first (i.e. largest); updates n, and appends to output



                                                                                  Try it online!






                                                                                  share|improve this answer











                                                                                  $endgroup$









                                                                                  • 1




                                                                                    $begingroup$
                                                                                    Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                                                                                    $endgroup$
                                                                                    – Giuseppe
                                                                                    Apr 3 at 13:15






                                                                                  • 1




                                                                                    $begingroup$
                                                                                    That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                                                                                    $endgroup$
                                                                                    – Aaron Hayman
                                                                                    Apr 3 at 13:23














                                                                                  1












                                                                                  1








                                                                                  1





                                                                                  $begingroup$


                                                                                  R, 67 65 bytes



                                                                                  -2 bytes thanks to Giuseppe



                                                                                  k=scan();o=1;i=10^(k:0);while(T<k)o=c(o,T<-T+i[i<=T&i+T<=k][1]);o


                                                                                  Pretty simple. It takes a set of powers of 10 beyond what would be needed in reverse order i.



                                                                                  (I would prefer to use i=10^rev(0:log10(k)) instead of i=10^(k:0) since the latter is computationally ineffecient, but golf is golf!).



                                                                                  Then in a while loop, applies the conditions to i and takes the first (i.e. largest); updates n, and appends to output



                                                                                  Try it online!






                                                                                  share|improve this answer











                                                                                  $endgroup$




                                                                                  R, 67 65 bytes



                                                                                  -2 bytes thanks to Giuseppe



                                                                                  k=scan();o=1;i=10^(k:0);while(T<k)o=c(o,T<-T+i[i<=T&i+T<=k][1]);o


                                                                                  Pretty simple. It takes a set of powers of 10 beyond what would be needed in reverse order i.



                                                                                  (I would prefer to use i=10^rev(0:log10(k)) instead of i=10^(k:0) since the latter is computationally ineffecient, but golf is golf!).



                                                                                  Then in a while loop, applies the conditions to i and takes the first (i.e. largest); updates n, and appends to output



                                                                                  Try it online!







                                                                                  share|improve this answer














                                                                                  share|improve this answer



                                                                                  share|improve this answer








                                                                                  edited Apr 3 at 13:41

























                                                                                  answered Apr 3 at 13:08









                                                                                  Aaron HaymanAaron Hayman

                                                                                  3516




                                                                                  3516








                                                                                  • 1




                                                                                    $begingroup$
                                                                                    Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                                                                                    $endgroup$
                                                                                    – Giuseppe
                                                                                    Apr 3 at 13:15






                                                                                  • 1




                                                                                    $begingroup$
                                                                                    That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                                                                                    $endgroup$
                                                                                    – Aaron Hayman
                                                                                    Apr 3 at 13:23














                                                                                  • 1




                                                                                    $begingroup$
                                                                                    Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                                                                                    $endgroup$
                                                                                    – Giuseppe
                                                                                    Apr 3 at 13:15






                                                                                  • 1




                                                                                    $begingroup$
                                                                                    That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                                                                                    $endgroup$
                                                                                    – Aaron Hayman
                                                                                    Apr 3 at 13:23








                                                                                  1




                                                                                  1




                                                                                  $begingroup$
                                                                                  Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                                                                                  $endgroup$
                                                                                  – Giuseppe
                                                                                  Apr 3 at 13:15




                                                                                  $begingroup$
                                                                                  Save a byte using T instead of n; it should be 2 but I don't think that TRUE is acceptable output for k=1, so we set o=+T. Try it!
                                                                                  $endgroup$
                                                                                  – Giuseppe
                                                                                  Apr 3 at 13:15




                                                                                  1




                                                                                  1




                                                                                  $begingroup$
                                                                                  That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                                                                                  $endgroup$
                                                                                  – Aaron Hayman
                                                                                  Apr 3 at 13:23




                                                                                  $begingroup$
                                                                                  That is horrendous coding, I like it. incidently, I can set o=1, and get that second byte.
                                                                                  $endgroup$
                                                                                  – Aaron Hayman
                                                                                  Apr 3 at 13:23











                                                                                  1












                                                                                  $begingroup$


                                                                                  Jelly, 12 bytes



                                                                                  1+«ạæḟ⁵«Ɗɗ¥Ƭ


                                                                                  Try it online!






                                                                                  share|improve this answer









                                                                                  $endgroup$


















                                                                                    1












                                                                                    $begingroup$


                                                                                    Jelly, 12 bytes



                                                                                    1+«ạæḟ⁵«Ɗɗ¥Ƭ


                                                                                    Try it online!






                                                                                    share|improve this answer









                                                                                    $endgroup$
















                                                                                      1












                                                                                      1








                                                                                      1





                                                                                      $begingroup$


                                                                                      Jelly, 12 bytes



                                                                                      1+«ạæḟ⁵«Ɗɗ¥Ƭ


                                                                                      Try it online!






                                                                                      share|improve this answer









                                                                                      $endgroup$




                                                                                      Jelly, 12 bytes



                                                                                      1+«ạæḟ⁵«Ɗɗ¥Ƭ


                                                                                      Try it online!







                                                                                      share|improve this answer












                                                                                      share|improve this answer



                                                                                      share|improve this answer










                                                                                      answered Apr 3 at 18:11









                                                                                      Erik the OutgolferErik the Outgolfer

                                                                                      33k429106




                                                                                      33k429106























                                                                                          1












                                                                                          $begingroup$


                                                                                          Pip, 27 bytes



                                                                                          Wa>Po+:y/t*Y1Ty>o|o+y>ay*:t


                                                                                          Try it online!



                                                                                          In pseudocode:



                                                                                          a = args[0]
                                                                                          o = 1
                                                                                          print o
                                                                                          while a > o {
                                                                                          y = 1
                                                                                          till y > o || o + y > a
                                                                                          y *= 10
                                                                                          o += y / 10
                                                                                          print o
                                                                                          }


                                                                                          I'm pretty pleased with the golfing tricks I was able to apply to shorten this algorithm. By initializing, updating, and printing stuff in the loop header, I was able to avoid needing curly braces for the loop body. There's probably a golfier algorithm, though.






                                                                                          share|improve this answer









                                                                                          $endgroup$


















                                                                                            1












                                                                                            $begingroup$


                                                                                            Pip, 27 bytes



                                                                                            Wa>Po+:y/t*Y1Ty>o|o+y>ay*:t


                                                                                            Try it online!



                                                                                            In pseudocode:



                                                                                            a = args[0]
                                                                                            o = 1
                                                                                            print o
                                                                                            while a > o {
                                                                                            y = 1
                                                                                            till y > o || o + y > a
                                                                                            y *= 10
                                                                                            o += y / 10
                                                                                            print o
                                                                                            }


                                                                                            I'm pretty pleased with the golfing tricks I was able to apply to shorten this algorithm. By initializing, updating, and printing stuff in the loop header, I was able to avoid needing curly braces for the loop body. There's probably a golfier algorithm, though.






                                                                                            share|improve this answer









                                                                                            $endgroup$
















                                                                                              1












                                                                                              1








                                                                                              1





                                                                                              $begingroup$


                                                                                              Pip, 27 bytes



                                                                                              Wa>Po+:y/t*Y1Ty>o|o+y>ay*:t


                                                                                              Try it online!



                                                                                              In pseudocode:



                                                                                              a = args[0]
                                                                                              o = 1
                                                                                              print o
                                                                                              while a > o {
                                                                                              y = 1
                                                                                              till y > o || o + y > a
                                                                                              y *= 10
                                                                                              o += y / 10
                                                                                              print o
                                                                                              }


                                                                                              I'm pretty pleased with the golfing tricks I was able to apply to shorten this algorithm. By initializing, updating, and printing stuff in the loop header, I was able to avoid needing curly braces for the loop body. There's probably a golfier algorithm, though.






                                                                                              share|improve this answer









                                                                                              $endgroup$




                                                                                              Pip, 27 bytes



                                                                                              Wa>Po+:y/t*Y1Ty>o|o+y>ay*:t


                                                                                              Try it online!



                                                                                              In pseudocode:



                                                                                              a = args[0]
                                                                                              o = 1
                                                                                              print o
                                                                                              while a > o {
                                                                                              y = 1
                                                                                              till y > o || o + y > a
                                                                                              y *= 10
                                                                                              o += y / 10
                                                                                              print o
                                                                                              }


                                                                                              I'm pretty pleased with the golfing tricks I was able to apply to shorten this algorithm. By initializing, updating, and printing stuff in the loop header, I was able to avoid needing curly braces for the loop body. There's probably a golfier algorithm, though.







                                                                                              share|improve this answer












                                                                                              share|improve this answer



                                                                                              share|improve this answer










                                                                                              answered Apr 5 at 6:47









                                                                                              DLoscDLosc

                                                                                              19.4k33990




                                                                                              19.4k33990























                                                                                                  0












                                                                                                  $begingroup$


                                                                                                  Japt, 18 bytes



                                                                                                  ÆT±ApTmTnU)sÊÉÃf§U


                                                                                                  Try it



                                                                                                  ÆT±ApTmTnU)sÊÉÃf§U     :Implicit input of integer U
                                                                                                  Æ :Map the range [0,U)
                                                                                                  T± : Increment T (initially 0) by
                                                                                                  A : 10
                                                                                                  p : Raised to the power of
                                                                                                  Tm : The minimum of T and
                                                                                                  TnU : T subtracted from U
                                                                                                  ) : End minimum
                                                                                                  s : Convert to string
                                                                                                  Ê : Length
                                                                                                  É : Subtract 1
                                                                                                  Ã :End map
                                                                                                  f :Filter
                                                                                                  §U : Less than or equal to U





                                                                                                  share|improve this answer









                                                                                                  $endgroup$


















                                                                                                    0












                                                                                                    $begingroup$


                                                                                                    Japt, 18 bytes



                                                                                                    ÆT±ApTmTnU)sÊÉÃf§U


                                                                                                    Try it



                                                                                                    ÆT±ApTmTnU)sÊÉÃf§U     :Implicit input of integer U
                                                                                                    Æ :Map the range [0,U)
                                                                                                    T± : Increment T (initially 0) by
                                                                                                    A : 10
                                                                                                    p : Raised to the power of
                                                                                                    Tm : The minimum of T and
                                                                                                    TnU : T subtracted from U
                                                                                                    ) : End minimum
                                                                                                    s : Convert to string
                                                                                                    Ê : Length
                                                                                                    É : Subtract 1
                                                                                                    Ã :End map
                                                                                                    f :Filter
                                                                                                    §U : Less than or equal to U





                                                                                                    share|improve this answer









                                                                                                    $endgroup$
















                                                                                                      0












                                                                                                      0








                                                                                                      0





                                                                                                      $begingroup$


                                                                                                      Japt, 18 bytes



                                                                                                      ÆT±ApTmTnU)sÊÉÃf§U


                                                                                                      Try it



                                                                                                      ÆT±ApTmTnU)sÊÉÃf§U     :Implicit input of integer U
                                                                                                      Æ :Map the range [0,U)
                                                                                                      T± : Increment T (initially 0) by
                                                                                                      A : 10
                                                                                                      p : Raised to the power of
                                                                                                      Tm : The minimum of T and
                                                                                                      TnU : T subtracted from U
                                                                                                      ) : End minimum
                                                                                                      s : Convert to string
                                                                                                      Ê : Length
                                                                                                      É : Subtract 1
                                                                                                      Ã :End map
                                                                                                      f :Filter
                                                                                                      §U : Less than or equal to U





                                                                                                      share|improve this answer









                                                                                                      $endgroup$




                                                                                                      Japt, 18 bytes



                                                                                                      ÆT±ApTmTnU)sÊÉÃf§U


                                                                                                      Try it



                                                                                                      ÆT±ApTmTnU)sÊÉÃf§U     :Implicit input of integer U
                                                                                                      Æ :Map the range [0,U)
                                                                                                      T± : Increment T (initially 0) by
                                                                                                      A : 10
                                                                                                      p : Raised to the power of
                                                                                                      Tm : The minimum of T and
                                                                                                      TnU : T subtracted from U
                                                                                                      ) : End minimum
                                                                                                      s : Convert to string
                                                                                                      Ê : Length
                                                                                                      É : Subtract 1
                                                                                                      Ã :End map
                                                                                                      f :Filter
                                                                                                      §U : Less than or equal to U






                                                                                                      share|improve this answer












                                                                                                      share|improve this answer



                                                                                                      share|improve this answer










                                                                                                      answered Apr 3 at 13:32









                                                                                                      ShaggyShaggy

                                                                                                      18.9k21768




                                                                                                      18.9k21768























                                                                                                          0












                                                                                                          $begingroup$


                                                                                                          C# (Visual C# Interactive Compiler), 123 122 bytes





                                                                                                          m=>{var a=new{1}.ToList();int s;for(;(s=a.Last())<m;)a.Add(s+(int)Math.Pow(10,(int)Math.Log(s<m-s?s:m-s,10)));return a;}


                                                                                                          Try it online!






                                                                                                          share|improve this answer











                                                                                                          $endgroup$


















                                                                                                            0












                                                                                                            $begingroup$


                                                                                                            C# (Visual C# Interactive Compiler), 123 122 bytes





                                                                                                            m=>{var a=new{1}.ToList();int s;for(;(s=a.Last())<m;)a.Add(s+(int)Math.Pow(10,(int)Math.Log(s<m-s?s:m-s,10)));return a;}


                                                                                                            Try it online!






                                                                                                            share|improve this answer











                                                                                                            $endgroup$
















                                                                                                              0












                                                                                                              0








                                                                                                              0





                                                                                                              $begingroup$


                                                                                                              C# (Visual C# Interactive Compiler), 123 122 bytes





                                                                                                              m=>{var a=new{1}.ToList();int s;for(;(s=a.Last())<m;)a.Add(s+(int)Math.Pow(10,(int)Math.Log(s<m-s?s:m-s,10)));return a;}


                                                                                                              Try it online!






                                                                                                              share|improve this answer











                                                                                                              $endgroup$




                                                                                                              C# (Visual C# Interactive Compiler), 123 122 bytes





                                                                                                              m=>{var a=new{1}.ToList();int s;for(;(s=a.Last())<m;)a.Add(s+(int)Math.Pow(10,(int)Math.Log(s<m-s?s:m-s,10)));return a;}


                                                                                                              Try it online!







                                                                                                              share|improve this answer














                                                                                                              share|improve this answer



                                                                                                              share|improve this answer








                                                                                                              edited Apr 3 at 16:56

























                                                                                                              answered Apr 3 at 16:50









                                                                                                              Expired DataExpired Data

                                                                                                              57314




                                                                                                              57314























                                                                                                                  0












                                                                                                                  $begingroup$


                                                                                                                  Prolog (SWI), 142 bytes



                                                                                                                  L-D-M:-append(L,[D],M).
                                                                                                                  N-L-C-X-R-I:-I=1,C is X*10,N-L-C-C-R-1;D is C+X,(D<N,L-D-M,N-M-D-X-R-I;D>N,N-L-C-(X/10)-R-0;L-D-R).
                                                                                                                  N-R:-N--0-1-R-1.


                                                                                                                  Try it online!



                                                                                                                  Explanation coming tomorrow or something






                                                                                                                  share|improve this answer









                                                                                                                  $endgroup$


















                                                                                                                    0












                                                                                                                    $begingroup$


                                                                                                                    Prolog (SWI), 142 bytes



                                                                                                                    L-D-M:-append(L,[D],M).
                                                                                                                    N-L-C-X-R-I:-I=1,C is X*10,N-L-C-C-R-1;D is C+X,(D<N,L-D-M,N-M-D-X-R-I;D>N,N-L-C-(X/10)-R-0;L-D-R).
                                                                                                                    N-R:-N--0-1-R-1.


                                                                                                                    Try it online!



                                                                                                                    Explanation coming tomorrow or something






                                                                                                                    share|improve this answer









                                                                                                                    $endgroup$
















                                                                                                                      0












                                                                                                                      0








                                                                                                                      0





                                                                                                                      $begingroup$


                                                                                                                      Prolog (SWI), 142 bytes



                                                                                                                      L-D-M:-append(L,[D],M).
                                                                                                                      N-L-C-X-R-I:-I=1,C is X*10,N-L-C-C-R-1;D is C+X,(D<N,L-D-M,N-M-D-X-R-I;D>N,N-L-C-(X/10)-R-0;L-D-R).
                                                                                                                      N-R:-N--0-1-R-1.


                                                                                                                      Try it online!



                                                                                                                      Explanation coming tomorrow or something






                                                                                                                      share|improve this answer









                                                                                                                      $endgroup$




                                                                                                                      Prolog (SWI), 142 bytes



                                                                                                                      L-D-M:-append(L,[D],M).
                                                                                                                      N-L-C-X-R-I:-I=1,C is X*10,N-L-C-C-R-1;D is C+X,(D<N,L-D-M,N-M-D-X-R-I;D>N,N-L-C-(X/10)-R-0;L-D-R).
                                                                                                                      N-R:-N--0-1-R-1.


                                                                                                                      Try it online!



                                                                                                                      Explanation coming tomorrow or something







                                                                                                                      share|improve this answer












                                                                                                                      share|improve this answer



                                                                                                                      share|improve this answer










                                                                                                                      answered Apr 4 at 13:52









                                                                                                                      ASCII-onlyASCII-only

                                                                                                                      4,4701338




                                                                                                                      4,4701338






























                                                                                                                          draft saved

                                                                                                                          draft discarded




















































                                                                                                                          If this is an answer to a challenge…




                                                                                                                          • …Be sure to follow the challenge specification. However, please refrain from exploiting obvious loopholes. Answers abusing any of the standard loopholes are considered invalid. If you think a specification is unclear or underspecified, comment on the question instead.


                                                                                                                          • …Try to optimize your score. For instance, answers to code-golf challenges should attempt to be as short as possible. You can always include a readable version of the code in addition to the competitive one.
                                                                                                                            Explanations of your answer make it more interesting to read and are very much encouraged.


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                                                                                                                          More generally…




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