using System;

namespace ConsoleApp5
{
    abstract class Function
    {
        public int x;
        public int y;

        public void F(int x, int y)
        {
            y = x;
        }

    }

    class Line : Function
    {
        public int a;
        public int b;

    }
    class Kub : Function
    {
        int c;
    }
    class Hyperbola : Function
    {

    }

    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
        }
    }
}