hdu 1267

hdu 1267 下沙的沙子有几粒？
独家

#include <iostream>

using namespace std;

int main()
{
    int m,n;
    while(cin>>m>>n)
    {
        double result1 = 1,sum1 = m+n ,sum2 = sum1 ;
        int aa = n;
        while(aa--)
        {
            result1 *= sum1  ;
            result1 /= n;
            sum1--;
            n--;
        }
        double result2 = 1 ;
        int bb = m+1 , cc =bb;
        while(bb--)
        {
            result2 *= sum2 ;
            result2 /= cc;
            cc--;
            sum2--;
        }
        printf("%.lf/n",result1 - result2);
    }
    return 0;
}