applebananapearcarrotcarrotbeardeerdeer
goatcowduckswanchickenmouseratbirdmouse
chocolatedogdogfishmousecatdeerbird
newyorkcalifornianewjerseymousecatdeerbird             

##</code><code>##

monksbicyclewindbikecars
computercomputerprinters
hellicopterairplaneshelf
chocolatedogdogfishmouse
printerprintermousecouch

.
.
goes on for another 600,000 lines

##</code><code>##

#!/usr/bin/perl -w
use strict;
my %lines;
my %lines2;
my $str2;
open(UNIQUES,"<$ARGV[0]");
open(ALL, "<$ARGV[1]");

while (<UNIQUES>)
    {
    $lines{$str1} = 1;
    }

while (<ALL>)
    {
    print $str1 if substr( $str1, 0, 24) eq ($str2); 
    next ($str2);
    }