#!/usr/bin/perl -l

# https://perlmonks.org/?node_id=1217669

use strict;
use warnings;

my @array = ('3','4','71','1', '-598', '-100203');

my ($answer) = map $_->[0],
  sort { $a->[1] <=> $b->[1] }
  grep $_->[1] >= 0,
  map [ $_, $array[$_] ], 0 .. $#array;

print $answer;