using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication3
{
    class Program
    {
        static void Main(string[] args)
        {

            string buf;
            double startX = 0, endX = 9, dx = 1, r, y = 0, x;
            Console.WriteLine("Введите r:");
            buf = Console.ReadLine();
            r = double.Parse(buf);

            Console.WriteLine("Введите x:");
            buf = Console.ReadLine();
            x = double.Parse(buf);

            for (x = startX; x <= endX; x += dx)
            {
                if ((x >= (2 * r + 3)) && (x < r + 3))
                    y = -(Math.Sqrt(r * r - Math.Pow(x + r + 3, 2)));
                if ((x >= r + 3) && (x < r))
                    y = x - 3;
                if ((x >= r) && (x < 0))
                    y = Math.Sqrt(r * r - x * x);
                if ((x >= 0) && (x < 3))
                    y = x + 3;
                if ((x >= 3) && (x <= 9))
                    y = 1 / 3 * x + 3;

                Console.WriteLine("x = {0}, y = {1}", x, y);

            }


        }
    }
}