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) {
        BufferedReader br
                    = new BufferedReader(new InputStreamReader(System.in));
            Scanner in = new Scanner(System.in);
            Solution s = new Solution();
            
            long i = in.nextLong();
            long j = in.nextLong();
            
            long min = Math.min(i,j);
            if (min == i) {
                long ans = i - 1 + i * (j-1);
                System.out.println(ans);
            } else {
                long ans = j - 1 + j * (i-1);
                System.out.println(ans);
            }
    }
}