LinkedListStack.cs

using System;

namespace AlgorithmsAndDataStructures.DataStructures.Stack;

public class LinkedListStack<T>
{
    private LinkedListStackNode<T> head;

    public LinkedListStack()
    {
        head = null;
    }

    public bool IsEmpty => head == null;

    public void Push(T value)
    {
        if (head == null)
        {
            head = new LinkedListStackNode<T> { Value = value };
        }
        else
        {
            var node = new LinkedListStackNode<T> { Value = value, Next = head };
            head = node;
        }
    }

    public T Pop()
    {
        if (IsEmpty) throw new ArgumentException("Stack is Empty");

        var value = head.Value;
        head = head.Next;
        return value;
    }

    public T Peak()
    {
        if (IsEmpty) throw new ArgumentException("Stack is Empty");
        return head.Value;
    }
}