#!/usr/bin/env perl

use strict;
use warnings;

use constant { COL0 => 0, COL2 => 1, ALL => 2 };

my ($col0, $col2) = ('', '');

print map {
    if ($col0 ne $_->[COL0]) {
        ($col0, $col2) = @{$_}[COL0,COL2];
        ("CLUSTER\n", $_->[ALL]);
    }
    elsif (substr($col2, 0, 3) ne substr($_->[COL2], 0, 3)) {
        $col2 = $_->[COL2];
        ("DELIMIT\n", $_->[ALL]);
    }
    else {
        $_->[ALL];
    }
}
sort {
    $a->[COL0] cmp $b->[COL0] || $b->[COL2] cmp $a->[COL2]
}
map {
    [ (split)[0,2], $_ ]
} <DATA>;

__DATA__
chrM:307    0   AGCGGGGA    129
chrM:307    0   AGCGGGGA    130
chrM:307    0   AGCGGGGA    129
chrM:308    0   AGCGGGGA    129
chrM:308    0   AGCGGGGA    130
chrM:308    0   AGCGGGGA    129
chrM:309    0   AGCGGGGA    129
chrM:309    0   AGCGGGGA    130
chrM:309    0   AGCGGGGA    129
chrM:307    0   TCAAAATG    130
chrM:308    0   TCAAAATG    130
chrM:309    0   TCAAAATG    130
chrM:307    0   TCACGGTG    130
chrM:308    0   TCACGGTG    130
chrM:309    0   TCACGGTG    130
chrM:307    0   TCAGCCTG    129
chrM:308    0   TCAGCCTG    129
chrM:309    0   TCAGCCTG    129
chrM:307    0   TCAGGGAG    130
chrM:308    0   TCAGGGAG    130
chrM:309    0   TCAGGGAG    130
chrM:307    1   TCAGGGTG    106
chrM:307    2   TCAGGGTG    130
chrM:307    2   TCAGGGTG    129
chrM:308    1   TCAGGGTG    106
chrM:308    2   TCAGGGTG    130
chrM:308    2   TCAGGGTG    129
chrM:309    1   TCAGGGTG    106
chrM:309    2   TCAGGGTG    130
chrM:309    2   TCAGGGTG    129