using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        List<int> myintList = new List<int> { 1, 4, 5, 6 };

​

        Func<List<int>, List<int>> SquareList = m => m.Select(x => x * x).ToList();

        List<int> result = SquareList(myintList);

        foreach (var item in result)

        {

            Console.WriteLine(item);

        }

    }

}