Q530: Binomial Showdown

// Run time: 0.000
#include <stdio.h>
void combination(int N, int M);
int main()
{
   int N, M;
   while (true)
   {
       scanf("%d%d", &N, &M);
       if (!N && !M)   break;

       if (M > N/2)
           M = N - M;

       combination(N, M);
   }
   return 0;
}

void combination(int N, int M)
{
   int i;
   double prod = 1;
   for ( i = 0; i < M; i++)
       prod *= double(N--)/double(i+1);

   printf("%.0lf\n", prod);
}