#include<stdio.h>
#define MAX 20

main()
{
    int i,j,n,p,r,primes[MAX];
    int *pntw, *pntr;
    long q;

    pntw = primes;
    n = 2;
    *pntw++ =2;
    *pntw++ =3;
    i = 5;

    do
    {
        pntr = primes;
        do{
            p = *pntr++;
            q = i/p;
            r = i - q * p;
            printf("p=%d\tq=%d\tr=%d\n",p,q,r);

        }while(r && i < q * q );

        printf("r=%d\n",r);

        if(r)
        {
            *pntw++ =i;
            n++;
            printf("n=%d\tr=%d\n",n,r);
        }
        i+=2;
        getch();
    }while (n < MAX);
    j=0;
    pntr = primes;
     for ( i=0;i<MAX;++i )
    {
        printf("%4d",*pntr++ );
        if ( ++j == 10 )
        {
            printf("\n");
            j=0;
        }
    }
}

在线等

你说的也许不错,但是在printf("p=%d\tq=%d\tr=%d\n",p,q,r);此句的输出中,R的值已经为零,怎么会到后面又变成了1呢?