using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

class Solution {
    static void Main(String[] args) {
        var arr = Console.ReadLine().Split(' ').Select(s=> long.Parse(s)).ToArray();
        long m = Math.Max(arr[0], arr[1]);
        long n = Math.Min(arr[0], arr[1]);
        
        long cuts = m-1 + m * (n-1);
        
        Console.WriteLine(cuts);
    }
}