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

my @unsorted_array = (	{ ID => 3, Distance => 2.3, RouteDistance => 4.3 },
						{ ID => 2, Distance => 1.5, RouteDistance => 2.8 },
						{ ID => 5, Distance => 2.1, RouteDistance => 0 },
						{ ID => 1, Distance => 1.7, RouteDistance => 2.5 });

my @sorted = sort { 
	if($a->{RouteDistance} == 0 || $b->{RouteDistance} == 0)
	{
		return ($a->{Distance} < $b->{Distance}) ? -1 : 1;
	}
	elsif ($a->{RouteDistance} == $b->{RouteDistance})
	{	
		return 0;
	}
	else
	{
		return ($a->{RouteDistance} < $b->{RouteDistance}) ? -1 : 1;
	}
} @unsorted_array;


foreach my $sorted_row (@sorted)
{
	print "ID: ".$sorted_row->{'ID'}." Distance: ".$sorted_row->{'Distance'}." RouteDistance: ".$sorted_row->{'RouteDistance'}."\n";
}