Hi, I want to have a one to one relationship.

e.g. "ger" <--> "german"
e.g. "ara" <--> "arabic"
e.g. "eng" <--> "english"

I always only know the left (e.g. "ger") or right value (e.g. "german") and I have to get the other value.

I tried to solve this problem with a hash. But then I have the problem that I do not get the key when I have the value. Here an example. 

#!/usr/bin/perl
use strict;
use warnings;

my %languages = ( "ger" => "german",
                  "ara" => "arabic",
                  "eng" => "english" );

# with the key it is easy to get to the value
foreach my $key (keys %languages )
{
    print "$key <--> $languages{$key}" . "\n";
}

# but how do I get key if I only have the value
# e.g. I know "german", but how do I get "ger"?

foreach my $value (values %languages )
{
    print "$value <--> ???" . "\n";
}

[download]

How would you solve this problem?

Thank you very much Dirk

In reply to One to one relationship by Dirk80

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