text: #! /usr/bin/python2.4
  
  # This Python program sorts and reformats the table of keywords in ref2.tex
  
  l = []
  try:
      while 1:
          l = l + raw_input().split()
  except EOFError:
      pass
  l.sort()
  for x in l[:]:
      while l.count(x) > 1: l.remove(x)
  ncols = 5
  nrows = (len(l)+ncols-1)/ncols
  for i in range(nrows):
      for j in range(i, len(l), nrows):
          print l[j].ljust(10),
      print
  