#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
#include <sstream>
#include <iostream>
#include <string>
#include <cstdio>
#include <cmath>

using namespace std;

int main() {

	long long N,sum=0,t;
	cin >> N;
	t = N;
	while (t != 0) {
		sum += t;
		t /= 2;
	}

	cout << max(N*2, N + (N/2*2)) - sum << endl;

	return 0;
}