using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        SortedList<int, string> planets = new SortedList<int, string>() {

            { 1, "Mercury" },

            { 2, "Venus" },

            { 3, "Earth" }

        };

        // LINQ Method Expression

        var planet = planets.Where(p => p.Key == 2).SingleOrDefault();

        Console.WriteLine($"{planet.Key}, {planet.Value}");

        Console.WriteLine("-----------------------");

        // LINQ Query Expression

        var planet1 = (from p in planets where p.Key == 3 select p).SingleOrDefault();

        Console.WriteLine($"{planet1.Key}, {planet1.Value}");

    }

}