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

int main() {
	ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	long long d; cin >> d;
	long long tmp = d / 2 - 1;
	for (long long i = tmp; i < tmp + 1000000; i++) {
		long long now = i;
		if (now == d) {
			cout << i << endl; return 0;
		}
		long long a = i;
		while (a > 0) {
			now += a / 2;
			if (now == d) {
				cout << i << endl; return 0;
			}
			a /= 2;
		}
		now += a;
		if (now == d) {
			cout << i << endl; return 0;
		}
	}
	cout << d << endl;
	return 0;
}