#include
void main()
{
    int i=1,r,a,b,c,d,m=7;
    while(i<10000)
    {
        r=i%13;
        if(r==0)
        {
            a=i%10;
            b=i/10%10;
            c=i/100%10;
            d=i/1000%10;
            if(a==m)
            {
                if(b==m) printf("%d\n",i);
                else if(c==m) printf("%d\n",i);
                else if(d==m) printf("%d\n",i);
            }
            else if(b==m)
            {
                if(c==m) printf("%d\n",i);
                else if(d==m) printf("%d\n",i);
            }
            else if(c==m) if(d==m) printf("%d\n",i);
        }
        i++;
    }
}
知道这个做什么的？