This rand func is not working!!

This is a discussion on This rand func is not working!! within the C Programming forums, part of the General Programming Boards category; hi thanks for checking this out: Code: void computerMove(char board[SIZE][SIZE]) { int x,y; x = rand()%3; y = rand()%3; board[x][y] ...

  1. #1
    Registered User
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    Oct 2007
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    This rand func is not working!!

    hi
    thanks for checking this out:

    Code:
    void computerMove(char board[SIZE][SIZE])
    {
    	int x,y;
    	x = rand()%3;
    	y = rand()%3;
    	board[x][y] = 'x';
    }
    this is just a simple random function for a computer to make a move in tic tac toe. Everytime i run the program i get the same randomly generated number [2][2]. I'm new to this so if it is blatantly obvious please make me feel retarded and then show me the light

  2. #2
    Deathray Engineer MacGyver's Avatar
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    Call srand() first. You need to call it at least once at the beginning of your program to seed the random number generator. On some systems, you have to call it once per thread. Don't worry about that for now. Somewhere near the start of your program, just put this:

    Code:
    srand(time(NULL));
    For what you're doing this should be sufficient. Make sure you include the proper header files.

  3. #3
    Algorithm Dissector iMalc's Avatar
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    You really should read the FAQ before posting. This is probably the most frequently asked question of all!

    Otherwise the poor FAQ writers will wonder why they even bothered...
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  4. #4
    and the hat of wrongness Salem's Avatar
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    I'm wondering...
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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