Answer:using System;
namespace Question
{
abstract class Figure
{
public abstract double Area();
}
class Circle : Figure
{
public double Radius { get; set; }
public override double Area()
{
return Math.PI * Radius * Radius;
}
}
class Rectangle : Figure
{
public double Length { get; set; }
public double Width { get; set; }
public override double Area()
{
return Length * Width;
}
}
class Cylinder : Figure
{
public double Radius { get; set; }
public double Height { get; set; }
public override double Area()
{
return Math.PI * Radius * Radius * Height;
}
}
class Program
{
static void DisplayMenu()
{
Console.WriteLine("Please select a figure");
Console.WriteLine("1 - Circle");
Console.WriteLine("2 - Rectangle");
Console.WriteLine("3 - Cylinder");
Console.WriteLine();
}
static int SelectFigure()
{
return int.Parse(Console.ReadLine());
}
static Figure GetFigure(int selectedFigure)
{
if (selectedFigure == 1)
return new Circle();
if (selectedFigure == 2)
return new Rectangle();
return new Cylinder();
}
static void InputCircleData(Circle circle)
{
Console.Write("radius = ");
circle.Radius = double.Parse(Console.ReadLine());
}
static void InputRectangleData(Rectangle rectangle)
{
Console.Write("length = ");
rectangle.Length = double.Parse(Console.ReadLine());
Console.Write("width = ");
rectangle.Width = double.Parse(Console.ReadLine());
}
static void InputCylinderData(Cylinder cylinder)
{
Console.Write("radius = ");
cylinder.Radius = double.Parse(Console.ReadLine());
Console.Write("height = ");
cylinder.Height = double.Parse(Console.ReadLine());
}
static void InputFigureData(Figure figure)
{
if (figure is Circle)
InputCircleData((Circle)figure);
else if (figure is Rectangle)
InputRectangleData((Rectangle)figure);
else
InputCylinderData((Cylinder)figure);
}
static void Main(string[] args)
{
DisplayMenu();
Console.Write("Your choice: ");
int selectedFigure = SelectFigure();
if (selectedFigure >= 1 && selectedFigure <= 3)
{
Figure figure = GetFigure(selectedFigure);
InputFigureData(figure);
Console.WriteLine();
Console.WriteLine(string.Format("Area = {0}", figure.Area()));
}
else
Console.WriteLine("Invalid choice");
Console.WriteLine();
Console.WriteLine();
Console.ReadKey();
Explanation:I hope this is right and i hope you understand :)and this is so difficult lol :)
