class Time2bb(hour:Int, minute:Int){
    //require(hour>=0 && minute>=0 && hour<24 && minute<60)
  if(hour<0 || hour>23 || minute<0 || minute>59) throw new IllegalArgumentException("blad")
    var ileMinOdPolnocy:Int=hour*60+minute
    def before(other:Time2bb):Boolean=
        ileMinOdPolnocy < other.ileMinOdPolnocy
        //override def toString = ileMinOdPolnocy+"min"
}