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


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