#!/usr/bin/python
# -*- coding: UTF-8 -*-
num=int(input())
count=0
if num>=1 and num<=1000:
 while num!=1:
	if num%2==0:
	  num=num/2
	else:
	  num=3*num+1
	count=count+1
 print count
else:
 print "请重新输入num的值."