Hello bananabread, and welcome to the Monastery!

You need a hash in which the keys are numbers and the values are the corresponding colours. If you already have the hash %colours as shown (and need to keep it for some other reason), you can create a reversed hash easily using Perl’s built-in reverse function. As an illustration:

use strict;
use warnings;
use Data::Dump;

my  %colours = ( blue => "1", green => "2", red => "3", pink => "4", p
+urple => "6" );
my  %reverse_colours = reverse %colours;
dd \%reverse_colours;

printf "The colour corresponding to %d is %s\n", 1, $reverse_colours{1
+};
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Output:

13:32 >perl 1703_SoPW.pl
{ 1 => "blue", 2 => "green", 3 => "red", 4 => "pink", 6 => "purple" }
The colour corresponding to 1 is blue

13:32 >
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See “How do I look up a hash element by value?” in perlfaq4.

Hope that helps,