#!/usr/bin/perl
use warnings;
use strict;

sub most_duplicated {
    my @numbers = @_;
    my %count;
    ++$count{$_} for @numbers;

    my @most_duplicated;
    my $max_count = 0;
    for my $n (keys %count) {
        if ($count{$n} > $max_count) {
            @most_duplicated = ($n);
            $max_count = $count{$n}

        } elsif ($count{$n} == $max_count) {
            push @most_duplicated, $n;
        }
    }
    return ($max_count, \@most_duplicated)
}

my @data
    = qw( 2 3 3 3 5 7 8 12 32 44 55 12 3 23 43 33 1 4 25 43 42 1 4 5 3 3 3 );
my ($count, $most_duplicated) = most_duplicated(@data);
print "@$most_duplicated occurred $count times.\n";