ACM篇：Uva 1942-- Paths on a Grid

#include <iostream>#include <cstdio>#include <algorithm>#include <cstdlib>using namespace std;unsigned _c(unsigned m, unsigned n){    double ret = 1.0;    while (m > 0)        ret *= (double)(n--) / double(m--);    return (unsigned)(ret+0.5);}int main(){    unsigned x, y;    while (scanf("%d%d", &x, &y) && (x || y))        printf("%d\n", _c(min(x, y), x + y));    return 0;}