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

my %hash1 = qw( 2 cars 1 motorcycle 4 balloons );
my %hash2 = qw( 5 airplanes 3 helicopters 6 skateboards );
# combine
my %hash = (%hash1, %hash2);
# print sorted
print map "$_ $hash{$_}\n", sort {$a<=>$b} keys %hash;