I have hashes with numbers as keys (it makes it easier to sort properly that way). I have an admin file which allows the user (or me) to delete an element of the hash.

What I'm trying to do is after the delete occurs, rebuild the hash again so there aren't any number gaps with the keys.

If you run the code below, the results will be: 

C:\Documents and Settings\my\Desktop>perl test.pl
0  ==== zero
1  ==== one
2  ==== three
3  ==== four
4  ==== four

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I don't know what's happened, but I should only have 0-3 left in my hash since I deleted {2} and for some reason it prints FOUR twice.

Where did I go wrong? 

#!/usr/bin/perl

use warnings;
use strict;

my %hash = (
            "0" => "zero",
            "1" => "one",
            "2" => "two",
            "3" => "three",
            "4" => "four"
            );

delete $hash{2};

my $num = "-1";

foreach (sort keys %hash) {
   $num++;
   my $value = $hash{$_};
   $hash{$num} = $value;
   }


foreach (sort keys %hash) {
   print "$_  ==== $hash{$_}\n";
   }

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In reply to rebuilding hashes by coldfingertips

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