#include<iostream>
using namespace std;

int main(){
  int n;
  while(1){
    cin >> n;
    if(n == 0) break;
    int cou=0;
    while(n != 1){
      if(n%2 == 0) n = n / 2;
      else n = n * 3 + 1;
      cou++;
    }
    cout << cou << endl;
  }
}