#!/usr/bin/perl

use strict;
use Data::Dumper;

my %record;
while(<DATA>) {
    chomp;
    my ($key, $sub_key, $val) = split ":";
    $record{$key}->{$sub_key}->{$val} = 1;
}

print Dumper \%record;

__DATA__
EQUIPMENT: BASEBALL: ACCESSORI
EQUIPMENT: BASEBALL: BALLS
EQUIPMENT: CYCLING
EQUIPMENT: GOLF: BAGS
EQUIPMENT: GOLF: BALLS
EQUIPMENT: OTHER BALL SPORTS:
EQUIPMENT: OTHER BALL SPORTS:
EQUIPMENT: RACQUET SPORTS: BAL
EQUIPMENT: RACQUET SPORTS: RAQ