#include <bits/stdc++.h>
#define endl '\n';
using namespace std;
typedef long long int LL;

int main()
{
  ios_base::sync_with_stdio(false);cin.tie(0);

  //freopen("input.in","r",stdin);

          	LL n,m;
          	cin>>n>>m;
          	cout<<min(n-1+n*(m-1),m-1+m*(n-1))<<endl;
  
  return 0;
}