Help with Pseudo numbers

This is a discussion on Help with Pseudo numbers within the C++ Programming forums, part of the General Programming Boards category; i have written a model program . though my actual program contains another set of questions(the questions i have used ...

  1. #1
    C++Pandit
    Join Date
    Jul 2008
    Posts
    49

    Help with Pseudo numbers

    i have written a model program . though my actual program contains another set of questions(the questions i have used here are real easy.)
    i have made use of srand and rand funtions
    here is my code
    Code:
    #include<iostream>
    #include<conio.h>
    #include <cstdlib> 
    #include <ctime> 
    
    using namespace std;
    main()
    {
          srand((unsigned)time(0));
          int question,score=0;
          int option1,option2,option3,option4;
          for(int a=1;a<4;a++)
          {
                  question=(rand()&#37;4)+1;
                  if(question==1)
                  {
                  cout<<"What is 8+5 ";
                  cin>>option1;
                  if(option1==13)
                  {
                  score++;
                  cout<<"Correct answer"<<endl;
                  cout<<"Score ="<<score<<endl;
                  }
                  else
                  {
                      score--;
                      cout<<"Bad answer"<<endl;
                      cout<<"Score ="<<score<<endl;
                  }
                  }
                  
                  if(question==2)
                  {
                  cout<<"What is 8+5"<<endl;
                  cin>>option1;
                  if(option1==13)
                  {
                  score++;
                  cout<<"Correct answer"<<endl;
                  cout<<"Score ="<<score<<endl;
                  }
                  else
                  {
                      score--;
                      cout<<"Bad answer"<<endl;
                      cout<<"Score ="<<score<<endl;
                  }
                  }
                  if(question==3)
                  {
                  cout<<"What is 8+4";
                  cin>>option2;
                  if(option2==12)
                  {
                  score++;
                  cout<<"Correct answer"<<endl;
                  cout<<"Score ="<<score<<endl;
                  }
                  else
                  {
                      score--;
                      cout<<"Bad answer"<<endl;
                      cout<<"Score ="<<score<<endl;
                  }
                  }
                  if(question==4)
                  {
                  cout<<"What is 8-5";
                  cin>>option3;
                  if(option3==3)
                  {
                  score++;
                  cout<<"Correct answer"<<endl;
                  cout<<"Score ="<<score<<endl;
                  }
                  else
                  {
                      score--;
                      cout<<"Bad answer"<<endl;
                      cout<<"Score ="<<score<<endl;
                  }
                  }
                  }
                 getch();
                  }
    everything is working fine.the problem arises when a question repeats itself. what should i do to make sure a question is asked only once?
    Last edited by Saimadhav; 10-14-2008 at 05:54 AM.

  2. #2
    Cat without Hat CornedBee's Avatar
    Join Date
    Apr 2003
    Posts
    8,892
    Instead of selecting a random question index on each iteration, put all possible question indices in an array. (Better yet, put data about the question and its answer in an array, instead of hard-coding each question.)
    Then, start the program by shuffling the array and afterwards just step through it in order.
    You can use std::random_shuffle for the shuffling.
    All the buzzt!
    CornedBee

    "There is not now, nor has there ever been, nor will there ever be, any programming language in which it is the least bit difficult to write bad code."
    - Flon's Law

  3. #3
    C++Pandit
    Join Date
    Jul 2008
    Posts
    49
    Code:
    main()
    {
         int option;
         char array[5];
         array[2]="5+6";
         cout<<array[2];
         cin>>option;
         if(option==11)
         {
                       cout<<"Good:";
                       }
                       getch();
                       }
    Is this code correct?
    If yes, how would I use rand() and srand() functions?
    Thanks.

  4. #4
    Registered User
    Join Date
    Jan 2005
    Posts
    7,317
    >> Is this code correct?
    No. You can't assign a string to an array element that holds a character. Can you switch to using the string class?

    Actually, CornedBee's solution is better in general, but it may be too advanced for you.

    You could just have a bool variable for all four questions. If the bool is false and rand() picks that question, then ask it and set the bool to true. If the bool is true, skip the question and make sure you don't increment a.

  5. #5
    Banned master5001's Avatar
    Join Date
    Aug 2001
    Location
    Visalia, CA, USA
    Posts
    3,685
    I have written a quick program that generates pseudo-numbers.

    Example:
    Code:
    #include <cstdlib>
    #include <ctime>
    #include <cctypes>
    #include <iostream>
    
    const char *names[] =
    {
      "Won",
      "Too",
      "Thrice",
      "For",
      "Phifth",
      "Firstteen"
    };
    
    int main(void)
    {
      size_t max = sizeof(names)/sizeof(*names);
      char c;
    
      srand(time(NULL));
    
      do
      {
    
    
        std::cout << names[rand()&#37;max] << std::endl << "Do you wish to continue?";
        std::cin >> c;
      } while(std::toupper(c) != 'N');
    
      return 0;
    }

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