using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        //Create a sorted list and add some keyValuePairs

        SortedList<int,string> sortedList1 = new SortedList<int,string>();

        sortedList1.Add(3, "Three");

        sortedList1.Add(4, "Four");

        sortedList1.Add(1, "One");

        sortedList1.Add(5, "Five");

        sortedList1.Add(2, "Two");

        //How to count how many keyValuePairs are in a sorted list

        Console.WriteLine("sortedList1 has "+sortedList1.Count + " items in the list");

        //for extra credit loop over the list and print the SortedList to the Console

        foreach(KeyValuePair<int,string> item in sortedList1 )

        {

            Console.WriteLine(item.Key + "" + item.Value);

        }

        SortedList<string,int> sortedList2 = new SortedList<string,int>();

        sortedList2.Add("one", 1);

        sortedList2.Add("two", 2);

        sortedList2.Add("three", 3);

        sortedList2.Add("four", 4);

        sortedList2.Add("five", 5);

        // Compile time error: cannot convert from <null> to <int>

        //sortedList2.Add("Five", null);

        //How to count how many items are in a sorted list2

        Console.WriteLine("sortedList2 has " + sortedList2.Count + " items in the list");

        //Loop over sortedList2 with a regular 'for loop', see sortedList3 below for a 'foreach' loop, you can use either one to loop over sortedList1 for extra credit

        //Hint: copy and paste this above and change sortedList2 -> sortedList1

        for (int i = 0; i < sortedList2.Count; i++)

        {

            Console.WriteLine("key: {0}, value: {1}", sortedList2.Keys[i], sortedList2.Values[i]);

        }

        //the ? after int lets us add in null values, without the ? it will say "cannot convert from <null> to <int>" and will not work

        //creates a sorted list with keyValuePairs

        SortedList<double,int?> sortedList3 = new SortedList<double,int?>()

        {

                {1.2, null},

                {3.6, 400},

                {7.1, 701}

        };

        //adds more keyValuePairs with .Add()

                sortedList3.Add(1.5, 100);

                sortedList3.Add(3.5, 200);

                sortedList3.Add(2.4, 300);

                sortedList3.Add(2.3, null);

                sortedList3.Add(1.1, null);

        //How to count how many items are in a sorted list 3

        Console.WriteLine("sortedList3 has " + sortedList3.Count + " items in the list");

        //How to loop over the sortedList3

        foreach(KeyValuePair<double,int?> kvp in sortedList3 )

        {

            Console.WriteLine("key: {0}, value: {1}", kvp.Key , kvp.Value );

​

        }

    }

}