#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    long long n, m;
    cin >> n >> m;
    long long f, s;
    f = n > m ? n : m;
    s = n <= m ? n : m;
    cout << (m - 1) + m * (n - 1);
    return 0;
}