OOP — Polymorphism with virtual #11 — C# Programming

Problem

Base Shape.Area() overridden in Circle.

Hints

abstract override Area()

Your practice code

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Solution

using System;

class Program
{
    static void Main()
    {
        Shape s = new Circle(3);
        Console.WriteLine(s.Area());

abstract class Shape { public abstract double Area(); }
class Circle : Shape {
    double r; public Circle(double r) => this.r = r;
    public override double Area() => Math.PI * r * r;
}
    }
}

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Explanation

Runtime polymorphism—virtual/override or abstract methods.