#!/usr/bin/perl -w
use strict;
use Data::Dumper::Simple;

my %first_two;

while (<DATA>) {
    chomp;
    my ($key, $remainder) = $_ =~ /([a-z]+\|[a-z]+)\|([a-z]+)/;
    if (exists $first_two{$key}) {
       $first_two{$key} .= ",$remainder";
    }
    else {
       $first_two{$key} = $_;
    }
}

print Dumper(%first_two);

__DATA__
aaa|bbb|ccc
ddd|eee|fff
ddd|eee|xxxxx
hhh|iiii|jjjjjj