Re: Interchanging hash values


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Re: Interchanging hash values

by DrManhattan (Chaplain)

on Apr 19, 2003 at 23:42 UTC ( [id://251738]=note: print w/replies, xml )

Need Help??

in reply to Interchanging hash values

There are a couple of ways you can improve on this. First, you can access the last element of an array by using the index -1. I.e.

$sort[scalar @sort - 1] == $sort[-1];
[download]

Also, you can swap the values of two variables without a temporary variable in the middle:

($a, $b) = ($b, $a);  # swap the values of $a and $b
[download]

So your code can be rewritten like so:

#!/usr/bin/perl -w
use strict;
use Data::Dumper;

my %hash = (Matt => 24,
            Dana => 19,
            Eric => 28,
            Sara => 20,
            John => 17,
            Mike => 23,);

print Dumper \%hash;

my @sort = sort {$hash{$a} <=> $hash{$b}} keys %hash;
($hash{$sort[0]}, $hash{$sort[-1]})
     = ($hash{$sort[-1]}, $hash{$sort[0]});

print Dumper \%hash;
[download]

-Matt