~cpp 
#include <iostream>
using namespace std;
int f(int, int);
int main()
{
	int r, c;
	cout << "몇번째 행, 열 ? : ";
	cin >> r >> c;
	cout << f(c, r) << endl;
	return 0;
}
int f(int a, int b) //a가 열 b가 행
{
	if (a > b)
		return 0;
	else if (a == 1 || a == b + 1)
		return 1;
	else
		return f(a, b - 1) + f(a - 1, b - 1);
}













