misod_000@miso-T430s ~ $ ./sosu kazu=>1 1 is prime misod_000@miso-T430s ~ $ ./sosu kazu=>1 1 is not prime

gistfile1.c

#include <stdio.h>
#include <stdlib.h>

int main()
{
        int i;
        srand((unsigned int)time(NULL));
        printf("kazu=>");
        scanf("%d", &i);
        if ((rand() % 2) == 1)
                printf("%d is prime\n", i);
        else
                printf("%d is not prime\n", i);
        return;
}