#!/usr/bin/perl -w
use strict;

my @regfile = <DATA>;

my %uniques = ();

foreach my $i (@regfile) {
    my ($email, $name, $date, $format) = split (/\|/, $i);
    $uniques{$email.$name.$date.$format}++;
    print "$email\|$name\|$date\|$format" 
        unless $uniques{$email.$name.$date.$format} > 1;
}

__DATA__
dummy@fake.com|John|10-10-2000|XZXXXXXXXXX
dummy2@fake.com|Joe|11-10-2000|XXXXXXXXXXX
alone@dunno.com|Jim|10-09-2000|YYYYYYYYYYYYY
dummy2@fake.com|Joe|11-10-2000|XXXXXXXXXXX

##</code><code>##

dummy@fake.com|John|10-10-2000|XZXXXXXXXXX
dummy2@fake.com|Joe|11-10-2000|XXXXXXXXXXX
alone@dunno.com|Jim|10-09-2000|YYYYYYYYYYYYY

##</code><code>##

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