#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    long long n,m;
    cin>>n>>m;
    long long l=n<=m?n:m;
    long long h=n<=m?m:n;
    cout<<(h-1)+(h*(l-1));
    return 0;
}