#include<algorithm>
#include<iostream>
#include<vector>
using namespace std;
typedef long long lint;
typedef vector<int>vi;
typedef pair<int,int>pii;
#define rep(i,n)for(int i=0;i<(int)(n);++i)

int main(){
  lint n;
  cin>>n;
  int cnt=0;
  while(n>1){
    if(n%2==1){
      n++;
      cnt++;
    }
    n/=2;
    cnt++;
  }
  cout<<cnt<<endl;
}