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

int main()
{
    long long N;
    cin >> N;
    vector<unsigned long long> T;
    while (N)
    {
        T.push_back(N);
        N /= 2;
    }
    int T_N = T.size();
    vector<unsigned long long> sum(T_N + 1);
    for (int i = 1; i <= T_N; i++)
    {
        sum[i] = sum[i - 1] + T[i - 1];
    }
    unsigned long long Max = 0;
    unsigned long long S = sum[T_N];
    for (int i = 0; i < T_N; i++)
    {
        Max = max(Max, sum[i] + (sum[i + 1] - sum[i]) * 2);
    }
    cout << Max - S;
}