#!usr/bin/env perl

use strict;
use warnings;

open (FILE1,"< file1");
while (!eof(FILE1))
{
chomp (my$element1 = (<FILE1>));
open (FILE3,"< file3");
while (!eof(FILE3))
{
my$element2 = (<FILE3>);
if ($element2 =~ /$element1/)
{print $element2;}
}
}
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