#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
using namespace std;

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

	long long ans = 0;
	if (N) {
		int cnt = 0;
		while (N) {
			ans += !(N & 1) * (1 << cnt);
			N >>= 1;
			cnt++;
		}
	}
	cout << ans << endl;

    return 0;
}