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


int main() {
    long long n,m,maxi,mini; cin >> n >> m; 
    maxi = max(n,m); mini = min(n,m);
    long long ans = (maxi - 1) + (maxi * (mini - 1));
    cout << ans << "\n";
    return 0;
}