using System; using static System.Console; using static System.Math; using static System.String; class Program { static void Main() { Write("Enter a circle's radius: "); var input = ReadLine(); if (!IsNullOrEmpty(input) && double.TryParse(input, out var radius)) { var c = new Circle(radius); string s = "\nInformation about the circle:\n"; s = s + Format(" Radius: {0:N2}\n", c.Radius); s = s + Format(" Diameter: {0:N2}\n", c.Diameter); s = s + Format(" Circumference: {0:N2}\n", c.Circumference); s = s + Format(" Area: {0:N2}\n", c.Area); WriteLine(s); } else { WriteLine("Invalid input..."); } } } public class Circle { public Circle(double radius) { Radius = radius; } public double Radius { get; set; } public double Diameter { get { return 2 * Radius; } } public double Circumference { get { return 2 * Radius * PI; } } public double Area { get { return PI * Pow(Radius, 2); } } } // The example displays the following output: // Enter a circle's radius: 12.45 // // Information about the circle: // Radius: 12.45 // Diameter: 24.90 // Circumference: 78.23 // Area: 486.95