random numbers

This is a discussion on random numbers within the C++ Programming forums, part of the General Programming Boards category; i used this function to get a random number and now the random numbers are picked in the same order ...

  1. #1
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    Question random numbers

    i used this function to get a random number and now the random numbers are picked in the same order every time the program is run. How can i change the order each time?

    int randMid(int low, int high)
    {
    return low+rand()%(high-low+1);
    }

  2. #2
    Fingerstyle Guitarist taylorguitarman's Avatar
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    change the "seed" to the number generator (rand).
    the rand() function is actually a pseudo random number generator meaning that the you get the same sequence each time with the same seed number. This is very useful in some programming areas such as games.

  3. #3
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    seed

    whats a seed

  4. #4
    &TH of undefined behavior Fordy's Avatar
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    srand()

    Go to the FAQs and the function is explained there

  5. #5
    Fingerstyle Guitarist taylorguitarman's Avatar
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    the number that starts the "random" generator.
    for C/C++ it is
    srand(int seed);
    usually you use the system time as the seed so the program will run differently each time.
    Otherwise you can pick a seed number for predictability.

  6. #6
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    ah

    i put srand(int time); in int main before the random number was chosen and i got a parse error

  7. #7
    ¡Amo fútbol!
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    include time.h at the top and use this srand(time(NULL))

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