using System;

using System.Collections.Concurrent;

public class Program

{

    private static ConcurrentDictionary<string, dynamic> cache =

        new ConcurrentDictionary<string, dynamic>();

    public void SetCache(string key, dynamic value)

    {

       cache.AddOrUpdate(key, value, (Func<string, dynamic, dynamic>) ((k, v) => value));

    }

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}