#include<stdio.h>
int main()
    {
    int n,i,j;

    printf("100-200之间的素数有：\n");
    for(n=101;n<200;n+=2)
        {
        for(i=2;i*i<n;i++)
            if(n%i==0)break;
            if(i*i>n)
                {
                if(j++%5==0)printf("\n");
                printf("%d\t",n);
                }
        }
    printf("\n");

    return 0;
    }

#include<stdio.h>
void main()
{
    int m, i,n=0;
    for (m=101;m<=200;m++)
    {
        for (i=2;i<m;i++)
            if (m%i == 0)
                break;
            if (i>=m)
            {
                printf(" %5d",m);
                n+=1;
                if (n % 7 == 0)
                    printf ("\n");
            }

    }
}

这也算一种方法吧