#!/usr/bin/perl

my @list = (1, 22, 101, 55, 402);
print "sort {a <=> b} \n";
@list = sort {$a <=> $b} @list;
 for my $val (@list) {
         print $val . "\n";
 }
print "sort {b <=> a} \n";
@list = sort {$b <=> $a} @list;
 for my $val (@list) {
         print $val . "\n";
 }



================================
$ perl sort.pl
sort {a <=> b}
1
22
55
101
402
sort {b <=> a}
402
101
55
22
1