/**
*计算组合数C(m,n)(m为下标,n为上标)
**/
#include<stdio.h>
//use the formula: c(m,n) = c(m-1,n) +c(m-1,n-1)
int cnr(int m,int n)
{
if(m == n||0 ==n)
return 1;
else
return cnr(m-1,n)+(m-1,n-1);
}
int main()
{
int m,n;
printf("please input m, n :\n");
scanf("%d,%d",&m,&n);
printf("c(%d,%d) = %d ",m,n,cnr(m,n));
return 0;
}