C# Online Compiler | .NET Fiddle

using System;
using System.Collections.Generic;

public class Program
{
	public static void Main()
	{
		// initial array
		var list = new List<string>();
		Console.WriteLine("[0] Capacity: {0}", list.Capacity);
		Console.WriteLine("[0] Count: {0}", list.Count);
		// add 4 items...
		for (int i = 0; i < 4; i++)
		{
			list.Add(i.ToString());
		}

		// check capacity & count
		Console.WriteLine("[1] Capacity: {0}", list.Capacity);
		Console.WriteLine("[1] Count: {0}", list.Count);
		// add another 4 items...
		for (int i = 0; i < 4; i++)
		{
			list.Add(i.ToString());
		}

		// check capacity & count
		Console.WriteLine("[2] Capacity: {0}", list.Capacity);
		Console.WriteLine("[2] Count: {0}", list.Count);
		// now, add only 1 item
		list.Add("hello");
		for (int i = 0; i < 6; i++)
		{
			list.Add(i.ToString());
		}

		// capacity & count might be different
		Console.WriteLine("[3] Capacity: {0}", list.Capacity);
		Console.WriteLine("[3] Count: {0}", list.Count);
		// then call TrimExcess() method...
		list.TrimExcess();
		// now, we know what capacity means
		Console.WriteLine("[4] Capacity: {0}", list.Capacity);
		Console.WriteLine("[4] Count: {0}", list.Count);
		// finally, we clear all items in the list
		list.Clear();
		// see what we get the capacity
		Console.WriteLine("[5] Capacity: {0}", list.Capacity);
		Console.WriteLine("[5] Count: {0}", list.Count);
	}
}

 
using System;
using System.Collections.Generic;
​
public class Program
{
    public static void Main()
    {
        // initial array
        var list = new List<string>();
        Console.WriteLine("[0] Capacity: {0}", list.Capacity);
        Console.WriteLine("[0] Count: {0}", list.Count);
        // add 4 items...
        for (int i = 0; i < 4; i++)
        {
            list.Add(i.ToString());
        }
​
        // check capacity & count
        Console.WriteLine("[1] Capacity: {0}", list.Capacity);
        Console.WriteLine("[1] Count: {0}", list.Count);
        // add another 4 items...
        for (int i = 0; i < 4; i++)
        {
            list.Add(i.ToString());