#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() {
    long int m,n;
    scanf("%ld %ld",&n,&m);
    if(n<m){
        printf("%ld",(n-1)+n*(m-1));
    }
    else{
        if(m==n)
            printf("%ld",(n-1)+n*(n-1));
        else
            printf("%ld",(m-1)+m*(n-1));
   
    }
        
        
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */    
    return 0;
}