#include <bits/stdc++.h>

#define REP(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))

using namespace std;

typedef int64_t ll;

const int INF = 1e8;
const double EPS = 1e-10;

int main() {
    ios_base::sync_with_stdio(false);
    ll a, b, sum = 0, ans = 0, x = 0;
    cin >> a;
    b = a;
    while(a) {
        sum += a;
        a /= 2LL;
    }
    
    while(b) {
        x += b;
        ans = max(ans, x+b-sum);
        b /= 2LL;
    } 

    cout << ans << endl;

}