#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 n, m;
    cin >> n >> m;
    
    long cuts = ((n - 1) * m) + (m - 1);
    
    cout << cuts;
    
    return 0;
}