How to find a DFA for combinations of even and odd occurrences $0,1$?












1















Let $L$ be a language over ${0,1}$ whose Nerode equivalence classes are:
$$
{w|#_0(w)mod2=0quadlandquad #_1(w)mod2=0}\
{w|#_0(w)mod2=0quadlandquad #_1(w)mod2=1}\
{w|#_0(w)mod2=1quadlandquad #_1(w)mod2=1}\
{w|#_0(w)mod2=1quadlandquad #_1(w)mod2=0}
$$

($#_0(w)mod2=0$ means that the number of zeroes in word $w$ is even).



Also $epsilon in L, 0,1,1110notin L$. Find DFA for the language.




First because there's a finite number of eq. classes by Nerode theorem we know that $L$ is regular so DFA exists for the language.



The solution to the problem is:



enter image description here



But I don't understand how the DFA accommodates all possible words in $L$.



1) For example what about $111$? It had even number of $0$'s and uneven number of $1$'s so it belongs to the second eq.class. But I don't see how we can arrive to this word using the DFA above.



2) What about the word $00011$? It belongs to the fourth equivalence class but I don't see how to arrive at this word using the DFA.










share|cite|improve this question



























    1















    Let $L$ be a language over ${0,1}$ whose Nerode equivalence classes are:
    $$
    {w|#_0(w)mod2=0quadlandquad #_1(w)mod2=0}\
    {w|#_0(w)mod2=0quadlandquad #_1(w)mod2=1}\
    {w|#_0(w)mod2=1quadlandquad #_1(w)mod2=1}\
    {w|#_0(w)mod2=1quadlandquad #_1(w)mod2=0}
    $$

    ($#_0(w)mod2=0$ means that the number of zeroes in word $w$ is even).



    Also $epsilon in L, 0,1,1110notin L$. Find DFA for the language.




    First because there's a finite number of eq. classes by Nerode theorem we know that $L$ is regular so DFA exists for the language.



    The solution to the problem is:



    enter image description here



    But I don't understand how the DFA accommodates all possible words in $L$.



    1) For example what about $111$? It had even number of $0$'s and uneven number of $1$'s so it belongs to the second eq.class. But I don't see how we can arrive to this word using the DFA above.



    2) What about the word $00011$? It belongs to the fourth equivalence class but I don't see how to arrive at this word using the DFA.










    share|cite|improve this question

























      1












      1








      1








      Let $L$ be a language over ${0,1}$ whose Nerode equivalence classes are:
      $$
      {w|#_0(w)mod2=0quadlandquad #_1(w)mod2=0}\
      {w|#_0(w)mod2=0quadlandquad #_1(w)mod2=1}\
      {w|#_0(w)mod2=1quadlandquad #_1(w)mod2=1}\
      {w|#_0(w)mod2=1quadlandquad #_1(w)mod2=0}
      $$

      ($#_0(w)mod2=0$ means that the number of zeroes in word $w$ is even).



      Also $epsilon in L, 0,1,1110notin L$. Find DFA for the language.




      First because there's a finite number of eq. classes by Nerode theorem we know that $L$ is regular so DFA exists for the language.



      The solution to the problem is:



      enter image description here



      But I don't understand how the DFA accommodates all possible words in $L$.



      1) For example what about $111$? It had even number of $0$'s and uneven number of $1$'s so it belongs to the second eq.class. But I don't see how we can arrive to this word using the DFA above.



      2) What about the word $00011$? It belongs to the fourth equivalence class but I don't see how to arrive at this word using the DFA.










      share|cite|improve this question














      Let $L$ be a language over ${0,1}$ whose Nerode equivalence classes are:
      $$
      {w|#_0(w)mod2=0quadlandquad #_1(w)mod2=0}\
      {w|#_0(w)mod2=0quadlandquad #_1(w)mod2=1}\
      {w|#_0(w)mod2=1quadlandquad #_1(w)mod2=1}\
      {w|#_0(w)mod2=1quadlandquad #_1(w)mod2=0}
      $$

      ($#_0(w)mod2=0$ means that the number of zeroes in word $w$ is even).



      Also $epsilon in L, 0,1,1110notin L$. Find DFA for the language.




      First because there's a finite number of eq. classes by Nerode theorem we know that $L$ is regular so DFA exists for the language.



      The solution to the problem is:



      enter image description here



      But I don't understand how the DFA accommodates all possible words in $L$.



      1) For example what about $111$? It had even number of $0$'s and uneven number of $1$'s so it belongs to the second eq.class. But I don't see how we can arrive to this word using the DFA above.



      2) What about the word $00011$? It belongs to the fourth equivalence class but I don't see how to arrive at this word using the DFA.







      proof-explanation equivalence-relations formal-languages automata






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Nov 24 at 9:13









      Yos

      1,137723




      1,137723






















          1 Answer
          1






          active

          oldest

          votes


















          1














          Not every equivalence class belongs to the language, otherwise the language would always be $Sigma^*$. Since $varepsilon in L$ and $0,1,1110 notin L$, we know that $L$ equals the first equivalence class. Therefore your examples are not counterexamples.






          share|cite|improve this answer





















            Your Answer





            StackExchange.ifUsing("editor", function () {
            return StackExchange.using("mathjaxEditing", function () {
            StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
            StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
            });
            });
            }, "mathjax-editing");

            StackExchange.ready(function() {
            var channelOptions = {
            tags: "".split(" "),
            id: "69"
            };
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function() {
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled) {
            StackExchange.using("snippets", function() {
            createEditor();
            });
            }
            else {
            createEditor();
            }
            });

            function createEditor() {
            StackExchange.prepareEditor({
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: true,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: 10,
            bindNavPrevention: true,
            postfix: "",
            imageUploader: {
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            },
            noCode: true, onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            });


            }
            });














            draft saved

            draft discarded


















            StackExchange.ready(
            function () {
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3011346%2fhow-to-find-a-dfa-for-combinations-of-even-and-odd-occurrences-0-1%23new-answer', 'question_page');
            }
            );

            Post as a guest















            Required, but never shown

























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            1














            Not every equivalence class belongs to the language, otherwise the language would always be $Sigma^*$. Since $varepsilon in L$ and $0,1,1110 notin L$, we know that $L$ equals the first equivalence class. Therefore your examples are not counterexamples.






            share|cite|improve this answer


























              1














              Not every equivalence class belongs to the language, otherwise the language would always be $Sigma^*$. Since $varepsilon in L$ and $0,1,1110 notin L$, we know that $L$ equals the first equivalence class. Therefore your examples are not counterexamples.






              share|cite|improve this answer
























                1












                1








                1






                Not every equivalence class belongs to the language, otherwise the language would always be $Sigma^*$. Since $varepsilon in L$ and $0,1,1110 notin L$, we know that $L$ equals the first equivalence class. Therefore your examples are not counterexamples.






                share|cite|improve this answer












                Not every equivalence class belongs to the language, otherwise the language would always be $Sigma^*$. Since $varepsilon in L$ and $0,1,1110 notin L$, we know that $L$ equals the first equivalence class. Therefore your examples are not counterexamples.







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Nov 24 at 9:24









                mrp

                3,77251537




                3,77251537






























                    draft saved

                    draft discarded




















































                    Thanks for contributing an answer to Mathematics Stack Exchange!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    Use MathJax to format equations. MathJax reference.


                    To learn more, see our tips on writing great answers.





                    Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


                    Please pay close attention to the following guidance:


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid



                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function () {
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3011346%2fhow-to-find-a-dfa-for-combinations-of-even-and-odd-occurrences-0-1%23new-answer', 'question_page');
                    }
                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    Plaza Victoria

                    In PowerPoint, is there a keyboard shortcut for bulleted / numbered list?

                    How to put 3 figures in Latex with 2 figures side by side and 1 below these side by side images but in...