using System;
using System.Collections;

namespace CS2026
{
    class ListMapping
    {
        delegate int Foo(int x);

        static ArrayList Map(Foo f, ArrayList list)
        {
            ArrayList result = new ArrayList();
            foreach (int element in list)
            {
                result.Add(f((int)element));
            }
            return result;
        }

        static int inc(int x) { return x + 1; }
        static int sqr(int x) { return x * x; }

        public static void Main()
        {
            Foo f = new Foo(inc);
            f += sqr;

            ArrayList aList = new ArrayList();
            aList.Add(1);
            aList.Add(2);
            aList.Add(3);

            Console.WriteLine("--- Before Map---");
            Console.Write("[");
            foreach (int element in aList)
            {
                Console.Write(element);
                Console.Write(", ");
            }
            Console.WriteLine("]");

            ArrayList newList = Map(f, aList);

            Console.WriteLine("--- After Map---");
            Console.Write("[");
            foreach (int element in newList)
            {
                Console.Write(element);
                Console.Write(", ");
            }
            Console.WriteLine("]");
            Console.ReadLine();
        }
    }
}