In the following code, the seed value is returned from the system clock by using the time() function.
#include <stdio.h> #include <stdlib.h> #include <time.h> int main() // w ww . j av a 2 s. co m { int r,a,b; srand((unsigned)time(NULL)); for(a=0;a<20;a++) { for(b=0;b<5;b++) { r=rand(); printf("%d\t",r); } putchar('\n'); } return(0); }
The time() function returns information about the current time of day.