Classes

class SimpleDate {

    constructor(year, month, day) {

     

        this.dt = new Date(year, month, day);

        this._year = year;

        this._month = month;

        this._day = day;

    }

    addDays(nDays) {

        dt += nDays;

    }

    getDay() {

        return this._day;

    }

}

class ComplicatedDate extends SimpleDate {

    constructor(year, month, day,Hour, Minute) {

        debugger;

    super(year, month, day);

    this.dt.setHours(this.dt.getHours()+Hour);

    this.dt.setMinutes(this.dt.getMinutes()+Minute);

    }

}

c = new     ComplicatedDate(1977,12,19,2,45);