#include <stdio.h>
#include <math.h>
main()
{
    int j = 0, n, k, i,flag;
    printf("\n");
    for (n = 3; n < 100; n = n + 2 )
    {
        k = sqrt((double)n);
        i = 2;
        flag = 0;
        while((i < = k)&&(flag ==0))

        {
            if(n % i == 0 ) falg= 1;
            i = i + 1;
        }
        if(flag == 0)
        {
            j = j +1;
            printf("%d", n);
            if (j % 10 = 0)
            printf("\n");
        }
    }
    printf("\n");
}

对啊
就是把1到100的素数打出来
每行十个