You can use the Graph module: 
#!/usr/bin/perl
use warnings;
use strict;

use Graph;

my @links = (qw( A   C
                 C   E
                 D   C
                 L   G
                 J   K
                 O   P
                 I   M
                 L   K
              ));

my $g = 'Graph::Undirected'->new;
$g->add_edge(splice @links, 0, 2) while @links;
print "@$_\n" for $g->connected_components;

[download]
($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: how can I group those links together? by choroba
in thread how can I group those links together? by plagent

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