using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

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

            { 1, "Mercury" },

            { 2, "Venus" },

            { 3, "Earth" }

        };

​

​

        planets.RemoveAt(1);

        //To print key and value

        foreach (var item in planets)

        {

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

        }

    }

}