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 s = new Scanner(System.in);
        long n = s.nextInt();
        long m = s.nextInt();
        
        long res = (m-1)+(n-1)*m;        
        long res2 = (n-1)+(m-1)*n;
        
        if(res<res2){
            System.out.print(res);
        }else{
            System.out.print(res2);
        }
    }
}