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


int main() {
    uint64_t n, m;
    cin >> n >> m;
    uint64_t ans1 = (n - 1) + n * (m - 1);
    uint64_t ans2 = (m - 1) + m * (n - 1);
    uint64_t ans = std::min(ans1, ans2);
    cout << ans << endl;
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    return 0;
}