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


int main() {
    long long int n, m;
    cin >> n >> m;
    cout << min((n-1) + n * (m-1), (m-1) + m * (n-1));
    return 0;
}