#include <bits/stdc++.h>

using namespace std;
using LL = long long;
using ULL = unsigned long long;
using VI = vector<int>;
using VL = vector<LL>;
using PII = pair<int, int>;
using PLL = pair<LL, LL>;

#define SZ(a) (int)a.size()
#define ALL(a) a.begin(), a.end()
#define MP make_pair
#define PB push_back
#define EB emplace_back
#define F first
#define S second
#define FOR(i, a, b) for (int i = (a); i<(b); ++i)
#define RFOR(i, b, a) for (int i = (b)-1; i>=(a); --i)
#define FILL(a, b) memset(a, b, sizeof(a))

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

	LL n, m;
	cin >> m >> n;
	LL total = n / 2 * (4 * m + m + m + 1);
	if (n % 2 == 0)
		total += 2 * m - 2;
	else
		total += 4 * m + m + 1;
	LL cnt = (n + 1) / 2 * m + n / 2 * (m - 1);
	cout << total - (cnt + 1) / 2 + 1 << '\n';
	
	
}