#include<iostream>
using namespace std;
int n, k, ans;
void f(int x, int sum, int cnt) {
	if (cnt == k && sum == n) {
		ans++;
		return;
	}
	if (cnt == k || sum == n) {
		return;
	}
	for (int i = x; i <= n; i++) {
		f(i, sum + i, cnt + 1);
	}
}
int main() {
	cin >> n >> k;
	f(1, 0, 0);
	cout << ans;
	return 0;
}