using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        IDictionary<int, bool> numberNames = new Dictionary<int, bool>();

        numberNames.Add(1,false);

        numberNames.Add(2,true);

        numberNames.Add(3,false);

        try {

            var c = numberNames[4];

        } catch (Exception e) {

            Console.WriteLine("Exception caught 1");

        }

        try {

            if(numberNames.ContainsKey(4)) {

                var c = numberNames[4];

            }

        } catch (Exception e) {

            Console.WriteLine("Exception caught 2");

        }

        Console.WriteLine("passed here");

    }

}