import java.util.Scanner;

public class Solution {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		
		Scanner s = new Scanner(System.in);
		long n = s.nextLong();
		long m = s.nextLong();
		
		long a = (n*(m-1)) + (n-1);
		long b = (m*(n-1)) + (m-1);
		
		if(a <b)
			System.out.println(a);
		else
			System.out.println(b);
	}

}