Average Runtime of this code












0












$begingroup$


I was working on a problem to find the average case of a for loop that has a 1 step in it. Each element in the input array has a distribution of {0...i} where i is the index of the element.



What threw me off was that, in the for loop there is an if statement that would prematurely end the for loop and this "if statement" would be executed if the value of the array was 50.



The Psuedocode looks somewhat like this:



for i from 0 to n-1:
do something
if L[i] == 50:
do something, and break


and the input of the array are distributed like this:



L[0] = {0}
L[1] = {0, 1}
L[2] = {0, 1, 2}
L[i] = {0, 1, 2, .., i}


With duplicates being allowed and they're independent.





I already realized that there really was no need to look at the summation before index 50 of the array. Further more, the probability of not getting the value of the array was quite obviously i/i+1, however with this being said I do not know how to fully use the expected value theorem to get the expected running time of the program.



I would just like a little tip to get me on track. I feel like im really close to solving this but yet so far, thank you










share|cite|improve this question









$endgroup$

















    0












    $begingroup$


    I was working on a problem to find the average case of a for loop that has a 1 step in it. Each element in the input array has a distribution of {0...i} where i is the index of the element.



    What threw me off was that, in the for loop there is an if statement that would prematurely end the for loop and this "if statement" would be executed if the value of the array was 50.



    The Psuedocode looks somewhat like this:



    for i from 0 to n-1:
    do something
    if L[i] == 50:
    do something, and break


    and the input of the array are distributed like this:



    L[0] = {0}
    L[1] = {0, 1}
    L[2] = {0, 1, 2}
    L[i] = {0, 1, 2, .., i}


    With duplicates being allowed and they're independent.





    I already realized that there really was no need to look at the summation before index 50 of the array. Further more, the probability of not getting the value of the array was quite obviously i/i+1, however with this being said I do not know how to fully use the expected value theorem to get the expected running time of the program.



    I would just like a little tip to get me on track. I feel like im really close to solving this but yet so far, thank you










    share|cite|improve this question









    $endgroup$















      0












      0








      0





      $begingroup$


      I was working on a problem to find the average case of a for loop that has a 1 step in it. Each element in the input array has a distribution of {0...i} where i is the index of the element.



      What threw me off was that, in the for loop there is an if statement that would prematurely end the for loop and this "if statement" would be executed if the value of the array was 50.



      The Psuedocode looks somewhat like this:



      for i from 0 to n-1:
      do something
      if L[i] == 50:
      do something, and break


      and the input of the array are distributed like this:



      L[0] = {0}
      L[1] = {0, 1}
      L[2] = {0, 1, 2}
      L[i] = {0, 1, 2, .., i}


      With duplicates being allowed and they're independent.





      I already realized that there really was no need to look at the summation before index 50 of the array. Further more, the probability of not getting the value of the array was quite obviously i/i+1, however with this being said I do not know how to fully use the expected value theorem to get the expected running time of the program.



      I would just like a little tip to get me on track. I feel like im really close to solving this but yet so far, thank you










      share|cite|improve this question









      $endgroup$




      I was working on a problem to find the average case of a for loop that has a 1 step in it. Each element in the input array has a distribution of {0...i} where i is the index of the element.



      What threw me off was that, in the for loop there is an if statement that would prematurely end the for loop and this "if statement" would be executed if the value of the array was 50.



      The Psuedocode looks somewhat like this:



      for i from 0 to n-1:
      do something
      if L[i] == 50:
      do something, and break


      and the input of the array are distributed like this:



      L[0] = {0}
      L[1] = {0, 1}
      L[2] = {0, 1, 2}
      L[i] = {0, 1, 2, .., i}


      With duplicates being allowed and they're independent.





      I already realized that there really was no need to look at the summation before index 50 of the array. Further more, the probability of not getting the value of the array was quite obviously i/i+1, however with this being said I do not know how to fully use the expected value theorem to get the expected running time of the program.



      I would just like a little tip to get me on track. I feel like im really close to solving this but yet so far, thank you







      real-analysis computational-complexity expected-value






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Jan 28 at 21:20









      Ace GokuAce Goku

      11




      11






















          0






          active

          oldest

          votes












          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%2f3091400%2faverage-runtime-of-this-code%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          0






          active

          oldest

          votes








          0






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes
















          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.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3091400%2faverage-runtime-of-this-code%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

          MongoDB - Not Authorized To Execute Command

          How to fix TextFormField cause rebuild widget in Flutter

          in spring boot 2.1 many test slices are not allowed anymore due to multiple @BootstrapWith