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();
        if(n == 1 && m == 1)
            System.out.println((n) * (m));
        else if (n == 1 && m > 1) {
            System.out.println((n) * (m - 1));
        } else if (m == 1 && n > 1) {
            System.out.println((n-1) * (m));
        } else if ( n > 1 && m > 1) {
            System.out.println((n-1) * (m-1));
        }
    }
}