#include <bits/stdc++.h>
using namespace std;

#define FOR(i,l,r) for(int i = (l);i < (r);i++)
#define ALL(x) (x).begin(),(x).end()
template<typename T> void chmax(T& a,const T& b){if(a < b) a = b;}
template<typename T> void chmin(T& a,const T& b){if(b < a) a = b;}
typedef long long ll;

ll N,M;

int main()
{
	cin >> N >> M;

	ll ans = min((N - 1) + (M - 1) * N,(M - 1) + (N - 1) * M);
	cout << ans << endl;

	return 0;
}