namespace 棧
{
 interface IStackDS<T> 
 {
  int Count { get; }
  int GetLength();
  bool IsEmpty();
  void Clear();
  void Push(T item);
  T Pop();
  T Peek();  
 }
}

namespace 棧
{
 class SeqStack<T> : IStackDS<T>
 {
  private T[] data; //棧
  private int top; //棧頂
  //構(gòu)造函數(shù)
  public SeqStack(int size) {
   data = new T[size];
   top = -1;
  }
  public SeqStack() : this(10)
  {
   data = new T[10];
   top = -1;
  }
  //棧的元素個數(shù)屬性
  public int Count
  {
   get
   {
    return top + 1;
   }
  }
  //清空棧的方法
  public void Clear()
  {
   top = -1;
  }
  //獲取棧的長度的方法
  public int GetLength()
  {
   return Count;
  }
  //查看棧頂元素是什么
  public T Peek()
  {
   if (top == -1)
   {
    Console.WriteLine("當(dāng)前棧沒有元素");
    return default(T);
   }
   return data[top];
  }
  //出棧（取出棧頂元素，并移除）
  public T Pop()
  {
   T temp = data[top];
   top--;
   return temp;
  }
  //入棧
  public void Push(T item)
  {
   data[top + 1] = item;
   top++;
  }
  //棧中是否源元素
  public bool IsEmpty()
  {
   return Count==0;
  }
 }
}

namespace 棧
{
 /// <summary>
 /// 鏈棧的節(jié)點
 /// </summary>
 /// <typeparam name="T"></typeparam>
 class Node<T>
 {
  private T data; //數(shù)據(jù)
  private Node<T> next; //指向下一個的引用
  //四個構(gòu)造函數(shù)，不是都有用，，以及上面兩個變量的屬性，
  public Node()
  {
   data = default(T);
   next = null;
  }
  public Node(T data)
  {
   this.data = data;
   next = null;
  }
  public Node(T data , Node<T> index)
  {
   this.data = data;
   this.next = index;
  }
  public Node(Node<T> index)
  {
   data = default(T);
   next = index;
  }
  public T Data
  {
   get { return data; }
   set { data = value; }
  }
  public Node<T> Next
  {
   get { return next; }
   set { next = value; }
  }
 }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace 棧
{
 class LinkStark<T> : IStackDS<T>
 {
  private Node<T> top; //棧頂元素節(jié)點
  private int count = 0; //棧里面的元素
  public int Count
  {
   get
   {
    return count;
   }
  }
  /// <summary>
  /// 清空棧中數(shù)據(jù)
  /// </summary>
  public void Clear()
  {
   count = 0;
   top = null;
  }
  /// <summary>
  /// 棧的長度
  /// </summary>
  /// <returns></returns>
  public int GetLength()
  {
   return Count;
  }
  /// <summary>
  /// 棧中是否有數(shù)據(jù)
  /// </summary>
  /// <returns></returns>
  public bool IsEmpty() 
  {
   return count == 0;
  }
  public T Peek()
  {
   return top.Data;
  }
  /// <summary>
  /// 出棧 取得棧頂元素然后刪除
  /// </summary>
  /// <returns></returns>
  public T Pop()
  {
   T data = top.Data;
   top = top.Next;
   count--;
   return data;
  }
  /// <summary>
  /// 入棧
  /// </summary>
  /// <param name="item"></param>
  public void Push(T item)
  {//把新添加的元素作為頭結(jié)點，就是棧頂
   Node<T> newNode = new Node<T>(item);
   newNode.Next = top;
   top = newNode;
   count++;
  }
 }
}

amespace 棧
{
 class Program
 {
  static void Main(string[] args)
  {
   //使用BCL中的棧
   //Stack<char> stack = new Stack<char>();
   //使用自己的棧
   // SeqStack<char> stack = new SeqStack<char>();
   //使用自己的鏈棧
   IStackDS<char> stack = new LinkStark<char>();
   stack.Push('a');
   stack.Push('b');
   stack.Push('c');
   Console.WriteLine("push后的數(shù)據(jù)個數(shù)"+ stack.Count);
   char temp = stack.Pop();
   Console.WriteLine("pop 之后數(shù)據(jù)是："+ temp);
   Console.WriteLine("pop 之后數(shù)據(jù)個數(shù)"+stack.Count);
   char temp2 = stack.Peek();
   Console.WriteLine("Peek 之后數(shù)據(jù)是：" + temp2);
   Console.WriteLine("Peek 之后數(shù)據(jù)個數(shù)" + stack.Count);
   Console.ReadKey();
  }
 }
}