//package HackerrankEasy;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

public class Solution {
public static void main(String[] args)throws IOException {
	BufferedReader in=new BufferedReader(new InputStreamReader(System.in));
	StringTokenizer st=new StringTokenizer(in.readLine());
	
	int x=Integer.parseInt(st.nextToken());
	int y=Integer.parseInt(st.nextToken());
	long max=Math.max(x, y);
	long min=Math.min(x, y);
	System.out.println(max-1+(min-1)*max);

}
}