Hello,

I have the following pseudo code, and I need to build a hash of unique keys, with arrays of unique values for each key. 

#!/usr/bin/perl -w

use strict;

my &hash;
while (<DATA>)
{
    $hash{$first} = $second; # only grabs the last value
}

while ((my $key, my $value) = each %construct) {
    print "The $key is: $value \n";
}

_DATA_
5    25
6    27
5    24
5    23
6    29    
6    30
4    22
5    25
6    27
4    22
4    21

[download]
This is what I want to end up with: 
The Key is: 5 
        25
        24
        23
        
The Key is: 6
        27
        29
        30
The Key is: 4
        22
        21

[download]

Any suggestions for a routine?

In reply to Unique keys for multiple values with a Hash by Anonymous Monk

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