import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
    Scanner sc=new Scanner(System.in);
        long m=sc.nextLong();
        long n=sc.nextLong();
        long count=0;
        if(m==1 && n!=1)
            {
             System.out.println(n-1);
            }
         else if(n==1 && m!=1)
            {
             System.out.println(m-1);
            }
        else if(m>n)
            {
            count+=n-1;
            count+=n*(m-1);
        System.out.println(count);
            }
        else if(n>m)
            {
            count+=m-1;
            count+=m*(n-1);
        System.out.println(count);
            }
        else if(m==n)
            {
           // count+=n-1;
            //count+=n*(m-1);
        System.out.println((m-1)*(n+1));
    }
    }
}