what is wrong with below? I was going through tutorial in perl.com and first I think it has typo where it compares b to b (where it should be a to b and b to a) but also when I run the code itself, it does NOT sort it correctly..
Can you please tell me why this code does not sort it correctly? 
http://www.perl.com/pub/a/2006/11/02/all-about-hashes.html



#!/usr/bin/perl -w

use strict;

my @list = qw(oranges oranges apple tomato tomato tomato tomato waterm
+elon watermelon watermelon);

my %histogram;
$histogram{$_}++ for @list;

my @unique = keys %histogram;

foreach (keys %histogram) {
  print "$_ ,  $histogram{$_}\n";
}


my @popular = (sort { $histogram{$b} <=> $histogram{$a} }  @unique)[0.
+.2];

print "@popular\n";

__END__
foreach (keys %histogram) {
  print "$_ ,  $histogram{$_}\n";
}
[root@myserver chaos]# ./!$
./perl.hashcrashcourse
oranges ,  2
watermelon ,  3
tomato ,  4
apple ,  1
tomato watermelon oranges




#!/usr/bin/perl -w

use strict;

my @list = qw(oranges oranges apple tomato tomato tomato tomato waterm
+elon watermelon watermelon);

my %histogram;
$histogram{$_}++ for @list;

my @unique = keys %histogram;

foreach (keys %histogram) {
  print "$_ ,  $histogram{$_}\n";
}


my @popular = (sort { $histogram{$a} <=> $histogram{$b} }  @unique)[0.
+.2];

print "@popular\n";

__END__
foreach (keys %histogram) {
  print "$_ ,  $histogram{$_}\n";
}
[root@myserver chaos]# ./!$
././perl.hashcrashcourse
oranges ,  2
watermelon ,  3
tomato ,  4
apple ,  1
apple oranges watermelon

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In reply to perl sort issue while going through article at perl.com by convenientstore

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