#include <bits/stdc++.h>
using namespace std;
vector<int> arr(101);
vector<int> dp(101);
vector<vector<int>> x(100001, dp);
int fn(int k, int id) {
  if (id == 0) return 1;
  if (x[k][id]) return x[k][id];
  for (int i = 1; i <= k - id; ++i) {
    x[k][id] += fn(k - i, id - 1);
  }
  return x[k][id];
}
int main() {
  int n, k;
  cin >> n >> k;
  cout << fn(k, n - 1);
}
