#!/usr/bin/env python
"""Get words from a text."""

import sys, re

r_word = re.compile(r"(?<!')[A-Za-z](?:[A-Za-z-]*[A-Za-z])?")

def main(f): 
   words = {}

   while 1: 
      line = f.readline()
      if not line: break
      line = line.replace('--', ' - ')
      for word in r_word.findall(line): 
         words[word.lower()] = 0
   keys = words.keys()
   keys.sort()
   return '\n'.join(keys)

if __name__=="__main__": 
   fn = sys.argv[1]
   f = open(fn, 'r')
   print main(f)
   f.close()