#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef pair<int,int> P;

int main(){ 
  int n;
  cin >> n;
  int res = 0;
  while ((1 << res) < n) res++;
  int cnt = res - 1;
  res += (1 << res) - n;
  res = min(res, cnt + n - (1 << cnt) + 1);
  cout << max(res, 0) << endl;
  return 0;
}