#include <bits/stdc++.h>

#define ll long long

using namespace std;

int n, m;
int main()
{
  #ifdef wws
    freopen("in", "r", stdin);
  #endif // wws
  cin >> n >> m;
  ll ans = min(n - 1 + 1ll * n * (m - 1), m - 1 + 1ll * m * (n - 1));
  cout << ans << endl;
  return 0;
}