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

using ll = long long;

int main(void) {
	ll N, M;
	cin >> N >> M;
	
	if(N % 2 == 0) {
		cout << N * M << "\n";
		return 0;
	}
	
	ll ans = 0, cnt = 0;
	for(int i = 29; i >= 0; --i) {
		if(M >> i & 1) {
			ans += (1LL << i) * (N - 1);
			++cnt;
		}
		else {
			ans += (1LL << i) * (cnt / 2) * 2;
		}
	}
	
	cout << ans << "\n";
	
	return 0;
}