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


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