#!/usr/bin/perl

use strict;
my($inset, $testinset, $teststring, $length, $matchcount, $count);

for($length = int(scalar(@ARGV) / 2); $length != 0; $length--){
  for($inset = 0; $inset < scalar(@ARGV) - $length + 1; $inset++){
    $teststring = buildstring($inset, $length);
    $matchcount = 1;

    if($teststring ne ""){
      for($testinset = $inset + $length; $testinset < scalar(@ARGV) - $length + 1; $testinset++){
	if($teststring eq buildstring($testinset, $length)){
	  $matchcount++;
	}
      }

      if($matchcount > 1){
	$ARGV[$inset] = "";
	for($count = 0; $count < $matchcount; $count++){
	  $ARGV[$inset] = "$ARGV[$inset]$teststring ";
	}
	for($count = 0; $count < $matchcount * $length - 1; $count++){
	  $ARGV[$inset + $count + 1] = "";
	}
      }
      $inset += $matchcount - 1;
    }
  }
}

for($count = 0; $count < scalar(@ARGV) + 1; $count++){
  if($ARGV[$count] ne ""){
    print "$ARGV[$count]\n";
  }
}

sub buildstring(){
  my($inset, $length) = @_;
  my($str, $count);

  $str = "";
  for($count = 0; $count < $length; $count++){
    $str = "$str$ARGV[$count + $inset]";
  }

  return $str;
}