#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 */   
    int n;
    int m;
    cin >> n >> m;
    // n > m
    if(n<m)
    {
        int a = n;
        n = m;
        m = a;
    }
    long int vys = m;
    vys *= n-1;
    vys += m-1;
    cout << vys;
    return 0;
}