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

public class Program
{
        public void Main()
        {
            Program.Try(Program.HandleArray_Where, "array.where");
            Program.Try(Program.HandleArray_Where_OrderBy, "array.where.orderby");
            Program.Try(Program.HandleList_Where, "list.where");
            Program.Try(Program.HandleList_Where_OrderBy, "list.where.orderby");
        }

        private static void Try(Action action, string text)
        {
            Console.WriteLine(text);

            try
            {
                action.Invoke();
            }
            catch (InvalidOperationException)
            {
                Console.WriteLine("Invalid operation");
            }

            Console.WriteLine();
            Console.WriteLine();
        }

        private static void HandleArray_Where()
        {
            IList<int> arr = new[] { 1, 2, 3, 4, 5 };
            var enumerable = arr.Where(item => item > 2);

            foreach (var item in enumerable)
            {
                arr[3] = 0;

                Console.WriteLine(item);
            }
        }

        private static void HandleArray_Where_OrderBy()
        {
            IList<int> arr = new[] { 1, 2, 3, 4, 5 };
            var orderedEnumerable = arr.Where(item => item > 2).OrderBy(asd => asd);

            foreach (var item in orderedEnumerable)
            {
                arr[3] = 0;

                Console.WriteLine(item);
            }
        }

        private static void HandleList_Where()
        {
            IList<int> list = new List<int> { 1, 2, 3, 4, 5 };
            var enumerable = list.Where(item => item > 2);

            foreach (var item in enumerable)
            {
                list[3] = 0;

                Console.WriteLine(item);
            }
        }

        private static void HandleList_Where_OrderBy()
        {
            IList<int> list = new List<int> { 1, 2, 3, 4, 5 };
            var orderedEnumerable = list.Where(item => item > 2).OrderBy(asd => asd);

            foreach (var item in orderedEnumerable)
            {
                list[3] = 0;

                Console.WriteLine(item);
            }
        }
}