$(document).on("click", ".cal_room_del", function() {

    $(this).closest('tr').remove();

    var tr_cnt = $('#tbl-room-select tbody tr').length;

    if (tr_cnt == 0) {

        $('#tbl-room-select').append('<tr><td class="text-center" colspan="6">선택해주세요.</td></tr>');

    }

});