#include <iostream>

using namespace std;

int main(){
  unsigned long long N, normal=0, skill=0;

  cin >> N;

  while(N > 0){
    if(skill < normal+N*2) skill = normal+N*2;
    normal += N;
    N /= 2;
  }

  cout << skill - normal << endl;

  return 0;
}