my $sql = qq|
    SELECT ID, tutorID, Latitude, Longitude, City, State, Zipcode
      FROM $table_tzips
     WHERE Zipcode IS not NULL
     ORDER BY tutorID
|;

my $last_tutor_id = "";
my $last_dist;
my @tutors;
my $sth = $dbh->prepare($sql);
$sth->execute();
while (my $tzips = $sth->fetchrow_hashref()) {
    my $tutor_id = $tzips->{tutorID};
    my $dist = calculate_distance(
        $clong, $clat,
        $tzips->{Longitude}, $tzips->{Latitude} );

    if ($last_tutor_id ne $tutor_id) {
        $last_tutor_id = $tutor_id;
        push @tutors, $tzips;
    }
    else {
        next if $last_dist <= $dist;
        $tutors[-1] = $tzips;
    }
    $tzips->{Dist} = $last_dist = $dist;
}
my @report_fields = qw( tzipID ID Dist City State Zipcode );

for my $tutor ( sort{ $a->{Dist} <=> $b{Dist} } @tutors) ) {
    print(join(', ', @{$tutor}{@report_fields}), "\n");
}