import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long n = sc.nextInt();
        long m = sc.nextInt();
        if(n>m)
        System.out.print(n-1+((m-1)*n));
        else
            System.out.print(m-1+((n-1)*m));
    }
}