#!/usr/bin/perl 
use strict;

my @Z;
my $last_stop;
while (<DATA>) {
    chomp;
    my @token = split ' ';
    if ( $token[0] eq 'Z' ) {
        if ($token[1] == $last_stop + 1) {
            $Z[-1]->[1] = $token[2];
        } else {
            push @Z, [ @token[1,2] ];
        }
        $last_stop = $token[2];
    }
}

print Dumper(\@Z);

__DATA__
Z  5   89
Z  92  102
Z  103 123
Z  126 150