using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Enter a figure: (1-circle, 2-sphere, 3-square, 4-rectangle, 5-parallelepiped)");

        int type = int.Parse(Console.ReadLine()); double R,a,b,c;

        switch(type)

        {case 1: { Console.WriteLine("Radius:"); R=double.Parse(Console.ReadLine()); 

                  if(R<=0) {goto et;} Console.WriteLine("Circle Perimeter: "+Circle.Perimeter(R)); Console.WriteLine("Circle Face: "+Circle.Face(R)); break;} 

         case 2: { Console.WriteLine("Radius:"); R=double.Parse(Console.ReadLine()); 

                  if(R<=0) {goto et;} Console.WriteLine("Sphere Surface: "+Sphere.Surface(R)); Console.WriteLine("Sphere Volume: "+Sphere.Volume(R)); break;} 

         case 3: { Console.WriteLine("Side A:"); a=double.Parse(Console.ReadLine()); 

                  if(a<=0) {goto et;} Console.WriteLine("Square Perimeter: "+Square.Perimeter(a)); Console.WriteLine("Square Face: "+Square.Face(a)); break;} 

         case 4: { Console.WriteLine("Side A:"); a=double.Parse(Console.ReadLine()); Console.WriteLine("Side B:"); b=double.Parse(Console.ReadLine()); 

                  if(a<=0 || b<=0) {goto et;} Console.WriteLine("Rectangle Perimeter: "+Rectangle.Perimeter(a,b)); Console.WriteLine("Rectangle Face: "+Rectangle.Face(a,b)); break;} 

         case 5: { Console.WriteLine("Side A:"); a=double.Parse(Console.ReadLine()); Console.WriteLine("Side B:"); b=double.Parse(Console.ReadLine()); Console.WriteLine("Side C:"); c=double.Parse(Console.ReadLine()); 

                  if(a<=0 || b<=0 || c<=0) {goto et;} Console.WriteLine("Parallelepiped Surface: "+Parallelepiped.Surface(a,b,c)); Console.WriteLine("Parallelepiped Volume: "+Parallelepiped.Volume(a,b,c)); break;} 

         default: {Console.WriteLine("Wrong number"); break;}

        } return;

        et: Console.WriteLine("Error");

    }

}

static class Circle 

{static private double pi = 3.1416; 

        static public double Perimeter(double R) { return 2 * pi * R; } 

        static public double Face(double R) { return pi *R *R; }

}

​

static class Sphere

{static private double pi = 3.1416; 

        static public double Surface(double R) { return 4 * pi * R * R; } 

        static public double Volume(double R) { return 4 * pi *R*R*R / 3; } 

}

static class Square

{       static public double Perimeter(double a) { return 4*a;}

        static public double Face(double a) { return a*a;}

}

static class Rectangle

{       static public double Perimeter(double a, double b) { return 2*(b+a);}

        static public double Face(double a, double b) { return b*a;}

}

static class Parallelepiped

{       static public double Surface(double a, double b, double c) { return 2*(a+b+c);}

        static public double Volume(double a, double b, double c) { return a*b*c;}

}