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

#define int long long

int N;

signed main()
{
	cin >> N;
	int sum = 0, ma = 0;
	while (N > 0)
	{
		sum += N;
		ma = max(ma, sum + N);
		N /= 2;
	}
	printf("%lld\n", ma - sum);
	return 0;
}