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How can i generate a random no within 100????

Posted on 2000-02-28
Medium Priority
Last Modified: 2010-05-18
Hi !

                           I used rand()  fn to generate a random no.How can i define the max limit for that....there
                   is  RAND_MAX....but i want to override that....

                   Can anyone pls help.....

                   Thanks in advance.
Question by:ceena
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Accepted Solution

ecebhume earned 200 total points
ID: 2567735
You don't need to override the RAND_MAX, all you need to do is once you get a random number, you mod it with 100, you'll get integer between 0 and 99 (add 1 to get b/w 1 and 100) or mod 101 to get b/w 0 and 100

// assume you do all initialize stuff up here with srand already
x = rand();

random_number = x % 100; // this gives you integer, 0 <= random_number <= 99


Expert Comment

ID: 2567803
If u want to increase the range of Random Numbers then u can use srand() function from Stdlib.h
or If u want to give ur own value then try opening stdlib.h and modify the value of RAND_MAX in it. Im not Very Sure of second thing Just Check it.
All the Best

Expert Comment

ID: 2567895
Changing the value of RAND_MAX is a very bad idea.
Go with ecubhume's solution

Expert Comment

ID: 2567918
Follow ecebhume's advice, wrap it in a small function:
  inline int
  random(int n)
    return rand() % n;

Author Comment

ID: 2567983
Thanks all.

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