using System;

​

namespace AreaOfVariousGeometricalShape            

{

    public class Shape

    {

        public static void Main(string[] args)

        {

            int choice;

            int radius;

            int length;

            int width;

            int based;

            int height;

            double area = 0;

            Console.Write("\n\n");

            Console.Write("Area of Various Geometrical Shape\n");

            Console.Write("-----------------------------------");

            Console.Write("\n\n");

            Console.WriteLine("Select an Option");

            Console.Write("[1] Area of circle\n");

            Console.Write("[2] Area of rectangle\n");

            Console.Write("[3] Area of triangle\n");

            Console.Write("Enter your option : ");

            choice = Convert.ToInt32(Console.ReadLine());

              switch (choice)

                {

                case 1:

                    Console.Write("Input radius of the circle : ");

                    radius = Convert.ToInt32(Console.ReadLine());

                    area = 3.14 * radius * radius;

                    Console.Write("The area is : {0:#,0.0000}\n", area);

                    break;   

                case 2:

                    Console.Write("Input length  of the rectangle : ");

                    length = Convert.ToInt32(Console.ReadLine());

                    Console.Write("Input  width of the rectangle : ");

                    width = Convert.ToInt32(Console.ReadLine());

                    area = length * width;

                    Console.Write("The area is : {0:#,0.0000}\n", area);

                    break;

                case 3:

                    Console.Write("Input the base of the triangle :");

                    based = Convert.ToInt32(Console.ReadLine());

                    Console.Write("Input the hight of the triangle :");

                    height = Convert.ToInt32(Console.ReadLine());

                    area = .5 * based * height;

                    Console.Write("The area is : {0:#,0.0000}\n", area);

                    break;

                default:

                    Console.WriteLine("Invalid option, just choose between 1 to 3 only!");

                    break;   

                } 

        }

    }    

}

​