#-*- coding:UTF-8 -*-
while True:
	n=int(raw_input())
	if n>=1 and n<=1000:
		break
	else:
		print "erro, agian!"
c=0
while n!=1:
	if n % 2:
		n=n*3+1
	else:
		n=n/2
	c=c+1   
print c