#!/usr/bin/perl 

use strict;
use warnings;

my @unique = ();
my %seen   = ();

foreach my $elem (@originalarray) {
    next if $seen{$elem}++;
    push @unique, $elem;
}

my ( @union, @intersection, @difference );
my %count;
my $element;

@union = @intersection = @difference = ();
%count = ();
foreach $element ( @originalarray, @unique ) { $count{$element}++ }
foreach $element ( keys %count ) {
    push @union, $element;
    push @{ $count{$element} > 1 ? \@intersection : \@difference }, $element;
}
while ( ( my $key, my $value ) = each(%count) ) {
    print "", ( $value - 2 ) . " " . $key if ( $value >= 3 );
}