#!/usr/bin/perl -l

# http://perlmonks.org/?node_id=1155716

use strict;
use warnings;

my $input = "abcdefghiaabccdjklm";
my $want = "efghijklm";

print $input;

$input =~ s/.(??{ -1 == index("$`$'", $&) && '(*FAIL)' })//g;

print $input;
print $want;
$input eq $want and print "Match!";
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