#include <iostream>
#include <fstream>
#include <cmath>
#include <vector>

using namespace std;

int f(int n){
    if (n == 1 or n == 2){
        return 1;
    }
    return f(n - 1) + f(n - 2);
}

int main()
{
    int n;
    cin >> n;
    int m;
    cin >> m;
    vector <vector <int> > dp(n, vector <int>(m, 0));
    for (int i = 0; i < m; i++){
        dp[0][i] = 1;
    }
    for (int j = 0; j < n; j++){
        dp[j][0] = 1;
    }
    for (int i = 1; i < n; i++){
        for (int j = 1; j < m; j++){
            dp[i][j] = dp[i - 1][j] + dp[i][j - 1];
        }
    }
    cout << dp[n - 1][m - 1];


}