#!/usr/bin/perl -lan
BEGIN {
    die "Usage: $0 Boundary.out DB.out"
        unless @ARGV == 2;
}

if ( $isDB ) {
    print $_, "\t" . grep { $_->[0] > $F[2] && $_->[1] < $F[3] }
                        @{$chr{$F[1]}}
}
else {
    push @{$chr{$F[0]}}, [ @F[1, 2] ];
    $isDB = eof;
}