#!/usr/bin/perl -w

use strict;
use Benchmark;

my $t = &Benchmark::timeit(1,'

my %seen;

my $f1="oddbigsort";    my $f2="oddbigsort2";
open (A,$f1);           open (B,$f2);
my @smaller_list = <A>; my @larger_list = <B>; 

if ($#larger_list < $#smaller_list) {
 @seen{@smaller_list} = ();
 delete @seen{@larger_list};
}
else {
 @seen{@larger_list} = ();
 delete @seen{@smaller_list};
}

my @culprits = keys %seen;
foreach (@culprits) {print "$_\n";}

close (A); close (B);

');

print timestr($t),"\n";