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