[CodeUp] #1925-(재귀함수) nCr (small) (관계기반 설계)

#include <iostream>
using namespace std;

int facto(int n,int l){
    if(n==l){
        return n;
    }
    else{
        return n*facto(n-1,l);
    }
}

int main(){
    int n,r;
    cin >> n >> r;
    if(n/2<r){
        r = n-r;
    }
    int ans = facto(n,n-r+1)/facto(r,1);
    cout << ans;
}