Inheritance, Interfaces and Polymorphism - ISC Class 12 Computer Science Questions with Answers, Page 2

class Overtime extends EmpSal
{
    int hours;
    double totsal;

    Overtime(String n, int c, double s, int h)
    {
        super(n, c, s);
        hours = h;
        totsal = 0.0;
    }

    void calSal()
    {
        if (hours > 40)
            totsal = salary + 5000;
        else if (hours >= 30 && hours <= 40)
            totsal = salary + 3000;
        else
            totsal = salary;
    }

    void show()
    {
        super.show();
        calSal();
        System.out.println("Overtime Hours: " + hours);
        System.out.println("Total Salary: " + totsal);
    }
}

class Volume extends Circle
{
    double height, volume;

    Volume(double r, double h)
    {
        super(r);
        height = h;
    }

    double calculate()
    {
        cal_area();
        volume = area * height;
        return volume;
    }

    void display()
    {
        super.display();
        System.out.println("Volume of Cylinder = " + volume);
    }
}

class Interest extends Bank
{
    double rate, time;

    Interest(String n, int a, double p, double r, double t)
    {
        super(n, a, p);
        rate = r;
        time = t;
    }

    double calculate()
    {
        double ci = principal * Math.pow((1 + rate / 100), time) - principal;
        return ci;
    }

    void display()
    {
        super.display();
        System.out.println("Rate of Interest = " + rate);
        System.out.println("Time Period = " + time);
        System.out.println("Compound Interest = " + calculate());
    }
}

class Supply extends Demand
{
    int pproduced;   // quantity produced
    double prate;    // cost per unit

    // parameterised constructor for both classes
    Supply(String id, String name, int d, int p, double r)
    {
        super(id, name, d);
        pproduced = p;
        prate = r;
    }

    // difference between amount of demand and amount produced
    double calculation()
    {
        return (prate * pdemand) - (prate * pproduced);
    }

    // displays all details and the difference
    void display()
    {
        super.display();
        System.out.println("Quantity produced: " + pproduced);
        System.out.println("Rate per unit: " + prate);
        System.out.println("Difference in amount of demand and supply: " + calculation());
    }
}

class Update extends Godown
{
    int pur_qty;
    double pur_rate;

    Update(String i, int q, double r, int pq, double pr)
    {
        super(i, q, r);
        pur_qty = pq;
        pur_rate = pr;
    }

    void update()
    {
        qty = qty + pur_qty;
        if (rate != pur_rate)
            rate = pur_rate;
        amt = qty * rate;
    }

    void display()
    {
        System.out.println("Stock before updating:");
        super.display();
        update();
        System.out.println("Stock after updating:");
        super.display();
    }
}

class Circle implements Shape
{
    double radius;

    Circle(int r)
    {
        radius = r;
    }

    public double area()
    {
        return 3.14 * radius * radius;
    }
}

class Rectangle implements Shape
{
    double length, breadth;

    Rectangle(int l, int b)
    {
        length = l;
        breadth = b;
    }

    public double area()
    {
        return length * breadth;
    }
}

class CalVol extends Base implements Data
{
    double ht;

    CalVol(double r, double h)
    {
        super(r);
        ht = h;
    }

    public double volume()
    {
        return pi * rad * rad * ht;
    }

    void show()
    {
        super.show();
        System.out.println("Height = " + ht);
        System.out.println("Volume of the cylinder = " + volume());
    }
}