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 in = new Scanner(System.in);
        int n = in.nextInt();
        int m = in.nextInt();
        int cuts = 0;
        if(n==1)
            cuts = m-1;
        else if(m==1)
            cuts = n-1;
        else if(n>m)
            cuts = (m-1)+(m)*(n-1);
          else if(m>n)
            cuts = (n-1)+(n)*(m-1);
            System.out.println(cuts);
    }
}