Thread: Generating Random Numbers

  1. #1
    Registered User
    Join Date
    Jan 2002
    Posts
    69

    Generating Random Numbers

    Can you tell me the code how to generate random numbers from 5-10 or tell me any links thanks.

  2. #2
    Unregistered
    Guest
    Code:
    #include <stdlib.h> 
    #include <stdio.h> 
    #include <time.h> 
    
    inline int rand_mid(int low, int high)
    {
        return (rand() * (high - low)) / RAND_MAX + low;
    }
    
    int main(void)
    {
        int x;
        srand(time(NULL));
        
        x = rand_mid(5, 10);
        printf("A random number from 5 to 10: %d\n", x);
    
        return 0;
    }

  3. #3
    Registered User
    Join Date
    Jan 2002
    Posts
    69

    Thanks

    Thanks just wondering can u redo it so it has comments just so i'm not mis-interpreting some parts of it.

  4. #4
    Unregistered
    Guest
    Code:
    #include <stdlib.h> //for rand, srand, and RAND_MAX 
    #include <stdio.h>  //for printf and you already know this ;p
    #include <time.h>   //for time to seed rand
    
    /*This function is declared as inline, meaning it is treated as a
    **macro instead of a function...this causes less overhead
    */
    inline int rand_mid(int low, int high)
    {
        /*take low out of high (subtract), then multiply the result
        **by a random number. Divide that result by the constant
        **RAND_MAX from stdlib and add low to that. The result is
        **a pseudo-random number within the bounds of low and high
        */
        return (rand() * (high - low)) / RAND_MAX + low;
    }
    
    int main(void)
    {
        int x;
        /*seed rand, this is done so that you don't get the same
        **set of random numbers every time you run the program
        **so you set the seed to the current time, which creates 
        **pretty good random numbers.
        */
        srand(time(NULL));
    
        /*pass 5 and 10 as low and high to rand_mid, then
        **assign the value returned to x and print it out
        */    
        x = rand_mid(5, 10);
        printf("A random number from 5 to 10: %d\n", x);
    
        return 0;
    }

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