#include <iostream> using namespace std; int main() { int n, m; cin >> n >> m; long long a[1005][1005] = {0}; for (int j = 1; j <= m; j++) a[1][j] = 1; for (int i = 1; i <= n; i++) a[i][1] = 1; for (int i = 2; i <= n; i++) { for (int j = 2; j <= m; j++) { a[i][j] = a[i-1][j] + a[i][j-1]; } } cout << a[n][m] << endl; return 0; }