<kmc> addquote <LKoen> kmc: it\'s 3am and instead of going to bed I just spent a looot of time reading a long article about circadian rythms and melatonin

#!/usr/bin/python
s=set()
try:
 while True:
  l=raw_input()
  if l not in s:
   s.add(l)
   print(l)
except EOFError:
 pass