#include<iostream>

using namespace std;

int ans;
int n, m;

int dfs(int x,int y)            //DFS
{
    if(x == m && y == n) ans ++;
    else
    {
        if(x < m) dfs(x + 1,y);
        if(y < n) dfs(x,y + 1);
    }
}

int main()
{
    cin >> n >> m;
    dfs(0, 0);

    cout << ans;

    return 0;
}