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

public class Solution {

    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        Scanner sc=new Scanner(System.in);
        long n=sc.nextLong();
        long m=sc.nextLong();
        long d;
        if(n>m)
        {
            d=m-1;
            d+=m*(n-1);
        }
        else
        {
            d=n-1;
            d+=n*(m-1);
        }
        System.out.println(d);
    }
}