#include <bits/stdc++.h>
using namespace std;

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