#include <bits/stdc++.h>
#define f first
#define s second
#define mp make_pair
#define pb push_back
#define all(c) (c).begin(), (c).end()
#define sqr(x) (x)*(x)
#define fname ""

using namespace std;

typedef long long ll;
const double eps = 1e-9;
const double PI = acos(-1.0);
const int inf = int (1e9+7);
const ll INF = (ll) 8e18+7;
const int mod = int (1e9+7);     
const int N = int (2e5+7);    

ll n, m;

int main () { 
   	//freopen(fname".in", "r", stdin);
   	//freopen(fname".out", "w", stdout);
   	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n >> m;
	cout << min((m - 1) + (n - 1) * m, (n - 1) + (m - 1) * n);
	return 0;
}