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

my %hashName = (a => 1, b => 2, c => 3, d=>3);

#sort keys by descending order of their value
my @keys = sort {$hashName{$b} <=> $hashName{$a}} keys %hashName;

my $max = $hashName{$keys[0]};

while (my $key = shift @keys)
{
   last if ($hashName{$key} < $max);
   print "$key=>$hashName{$key}\n";
}
__END__
c=>3
d=>3