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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;			
public class Program
{

	public static void Main()
	{
		var dict = new Dictionary<string, object>();        
        dict.Add("first", new object());
        dict.Add("second", new object());
        dict.Remove("first");
        dict.Add("third", new object());

        foreach (var entry in dict)
        {
            Console.WriteLine(entry.Key);
        }
	}
}