Compute the area of a circle in CSharp

using System;  //ww w  .  j a v a  2s  .  com
   
public class ComputeCircle {   
  static void Main() {   
    double radius; 
    double area; 
 
    radius = 1123.0; 
    area = radius * radius * 3.1416; 
 
    Console.WriteLine("Area is " + area); 
  }   
}