using System;

​

public class Program

{

    public static void Main()

    { 

        Console.WriteLine("Ingrese el radio de circunferencia ");

        double radio;

        double area;

        double pi = 3.14;

​

​

        radio = Convert.ToDouble( Console.ReadLine() );

        area = pi * Math.Pow(radio, 2) ;

​

        Console.WriteLine("El area de circunferencia es " + area);

​

    }

}