How to use function srand() with time.h? [duplicate]

Solution 1:

You need to call srand() once, to randomize the seed, and then call rand() in your loop:

#include <stdlib.h>
#include <time.h>

#define size 10

srand(time(NULL)); // randomize seed

for(i=0;i<size;i++)
    Arr[i] = rand()%size;

Solution 2:

Try to call randomize() before rand() to initialize random generator.

(look at: srand() — why call it only once?)

Solution 3:

If you chose to srand, it is a good idea to then call rand() at least once before you use it, because it is a kind of horrible primitive psuedo-random generator. See Stack Overflow question Why does rand() % 7 always return 0?.

srand(time(NULL));
rand();
//Now use rand()

If available, either random or arc4rand would be better.