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


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