Olá, tudo bom com você?

Espero que sim! Estou aqui para falar rapidamente de Pilhas e Filas. Bom, o C# possui no namespace System.Collections.Generic, duas classes genéricas, bem úteis, mas muito ignoradas: Stack<T> e Queue<T>.

O que você precisa saber de Queues e Stacks:

Queues implementas FIFO (First in, First Out), enquanto Stacks implementa LIFO (Last in, First Out).

Métodos e Propriedades mais relevantes

Comuns a Ambos

//
// Summary:
// Returns the object at the top of the System.Collections.Generic.Stack<T> or System.Collections.Generic.Queue<T>
// without removing it.
//
// Returns:
// The object at the top of the System.Collections.Generic.Stack<T> or System.Collections.Generic.Queue<T>.
//
// Exceptions:
// System.InvalidOperationException:
// The System.Collections.Generic.Stack<T> or The System.Collections.Generic.Queue<T> is empty.
public T Peek();

// Summary:
// Gets the number of elements contained in the System.Collections.Generic.Stack<T> or System.Collections.Generic.Queue<T>.
//
// Returns:
// The number of elements contained in the System.Collections.Generic.Stack<T> or System.Collections.Generic.Queue<T>.
public int Count { get; }

System.Collections.Generic.Queue<T>

//
// Summary:
// Adds an object to the end of the System.Collections.Generic.Queue<T>.
//
// Parameters:
// item:
// The object to add to the System.Collections.Generic.Queue<T>. The value can
// be null for reference types.
public void Enqueue(T item);

//
// Summary:
// Removes and returns the object at the beginning of the System.Collections.Generic.Queue<T>.
//
// Returns:
// The object that is removed from the beginning of the System.Collections.Generic.Queue<T>.
//
// Exceptions:
// System.InvalidOperationException:
// The System.Collections.Generic.Queue<T> is empty.
public T Dequeue();

System.Collections.Generic.Stack<T>

//
// Summary:
// Removes and returns the object at the top of the System.Collections.Generic.Stack<T>.
//
// Returns:
// The object removed from the top of the System.Collections.Generic.Stack<T>.
//
// Exceptions:
// System.InvalidOperationException:
// The System.Collections.Generic.Stack<T> is empty.
public T Pop();

//
// Summary:
// Inserts an object at the top of the System.Collections.Generic.Stack<T>.
//
// Parameters:
// item:
// The object to push onto the System.Collections.Generic.Stack<T>. The value
// can be null for reference types.
public void Push(T item);

Bom, era somente isso que eu queria passar. Vale a pena dar uma olhada em outras classes disponíveis no namespace System.Collections aconselho olhar:

System.Collections.Concurrent.ConcurrentQueue<T>

System.Collections.Concurrent.ConcurrentStack<T>

System.Collections.Generic.SortedSet<T>

System.Collections.Generic.SortedList<TKey, TValue>

System.Collections.Generic.LinkedList<T>

todos estão nos assemblies mscorlib ou System.

Era só isso!

Grande abraço!