using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace LinearList
{
  //定義線性表的行為，可供順序表類和單鏈表類繼承
  public interface IListDS<T>
  {
    int GetLength();
    void Insert(T item, int i);
    void Add(T item);
    bool IsEmpty();
    T GetElement(int i);
    void Delete(int i);
    void Clear();
    int LocateElement(T item);
    void Reverse();
  }
  //鏈表節(jié)點(diǎn)類
  class Node<T>
  {
    private T tData;
    private Node<T> nNext;
    public T Data
    {
      get { return this.tData; }
      set { this.tData = value; }
    }
    public Node<T> Next
    {
      get { return this.nNext; }
      set { this.nNext = value; }
    }
    public Node()
    {
      this.tData = default(T);
      this.nNext = null;
    }
    public Node(T t)
    {
      this.tData = t;
      this.nNext = null;
    }
    public Node(T t,Node<T> node)
    {
      this.tData = t;
      this.nNext = node;
    }
  }
  //該枚舉表示單鏈表Add元素的位置，分頭部和尾部?jī)煞N
  enum AddPosition {Head,Tail};
  //單鏈表類
  class LinkedList<T>:IListDS<T>
  {
    private Node<T> tHead;//單鏈表的表頭
    public Node<T> Head
    {
      get { return this.tHead; }
      set { this.tHead = value; }
    }
    public LinkedList()
    {
      this.tHead = null;
    }
    public LinkedList(Node<T> node)
    {
      this.tHead = node;
    }
    public void Add(T item,AddPosition p)//選擇添加位置
    {
      if (p == AddPosition.Tail)
      {
        this.Add(item);//默認(rèn)添加在末尾
      }
      else//從頭部添加會(huì)節(jié)省查找的開(kāi)銷，時(shí)間復(fù)雜度為O(1)不必每次都循環(huán)到尾部，這恰好是順序表的優(yōu)點(diǎn)
      {
        Node<T> node = this.Head;
        Node<T> nodeTmp = new Node<T>(item);
        if (node == null)
        {
          this.Head = nodeTmp;
        }
        else
        {
          nodeTmp.Next = node;
          this.tHead = nodeTmp;
        }
      }
    }
    #region IListDS<T> 成員
    public int GetLength()
    {
      Node<T> node = new Node<T>();
      int count = 0;
      node = this.tHead;
      while (node != null)
      {
        count++;
        node = node.Next;
      }
      return count;
    }
    public void Insert(T item, int i)//i最小從1開(kāi)始
    {
      Node<T> insertNode = new Node<T>(item, null);//實(shí)例化待添加的Node
      if (this.tHead == null && i == 1)
      {
        this.tHead = insertNode;
        return;
      }
      if (i < 1 || i > this.GetLength() || (this.tHead == null && i != 1))
      {
        Console.WriteLine("There are no elements in this linked list!");
        return;
      }
      int j = 1;
      Node<T> node = this.tHead;
      Node<T> nodeTmp;
      while (node != null && j < i)//循環(huán)結(jié)束時(shí)，保證node為第i個(gè)node
      {
        node = node.Next;
        j++;
      }
      nodeTmp = node.Next;//原來(lái)的單鏈表的第i+1個(gè)node
      node.Next = insertNode;//第i個(gè)node后的node修改為待插入的node
      insertNode.Next = nodeTmp;//待插入的node插入后，其后繼node為原來(lái)鏈表的第i+1個(gè)node
    }
    public void Add(T item)//添加至尾部，時(shí)間復(fù)雜度為O(n)，如果添加至頭部，則會(huì)節(jié)省循環(huán)的開(kāi)銷
    {
      Node<T> LastNode = new Node<T>(item, null);//實(shí)例化待添加的Node
      if (this.tHead == null)
      {
        this.tHead = LastNode;
      }
      else
      {
        Node<T> node = this.tHead;
        while (node.Next != null)
        {
          node = node.Next;
        }
        node.Next = LastNode;
      }
    }
    public bool IsEmpty()
    {
      return this.tHead == null;
    }
    public T GetElement(int i)//設(shè)i最小從1開(kāi)始
    {
      if (i < 1 || i > this.GetLength())
      {
        Console.WriteLine("The location is not right!");
        return default(T);
      }
      else
      {
        if (i == 1)
        {
          return this.tHead.Data;
        }
        else
        {
          Node<T> node = this.tHead;
          int j = 1;
          while (j < i)
          {
            node = node.Next;
            j++;
          }
          return node.Data;
        }
      }
    }
    public void Delete(int i)//設(shè)i最小從1開(kāi)始
    {
      if (i < 1 || i > this.GetLength())
      {
        Console.WriteLine("The location is not right!");
      }
      else
      {
        if (i == 1)
        {
          Node<T> node = this.tHead;
          this.tHead = node.Next;
        }
        else
        {
          Node<T> node = this.tHead;
          int j = 1;
          while (j < i-1)
          {
            node = node.Next;
            j++;
          }
          node.Next = node.Next.Next;
        }
      }
    }
    public void Clear()
    {
      this.tHead = null;//講thead設(shè)為null后，則所有后繼結(jié)點(diǎn)由于失去引用，等待GC自動(dòng)回收
    }
    public int LocateElement(T item)//返回值最小從1開(kāi)始
    {
      if (this.tHead == null)
      {
        Console.WriteLine("There are no elements in this linked list!");
        return -1;
      }
      Node<T> node = this.tHead;
      int i = 0;
      while (node != null)
      {
        i++;
        if (node.Data.Equals(item))//如果Data是自定義類型，則其Equals函數(shù)必須override
        {
          return i;
        }
        node = node.Next;
      }
      Console.WriteLine("No found!");
      return -1;
    }
    public void Reverse()
    {
      if (this.tHead == null)
      {
        Console.WriteLine("There are no elements in this linked list!");
      }
      else
      {
        Node<T> node = this.tHead;
        if (node.Next == null)//如果只有頭節(jié)點(diǎn)，則不作任何改動(dòng)
        {
        }
        else
        {
          Node<T> node1 = node.Next;
          Node<T> node2;
          while (node1 != null)
          {
            node2 = node.Next.Next;
            node.Next = node2;//可以發(fā)現(xiàn)node始終未變，始終是原來(lái)的那個(gè)頭節(jié)點(diǎn)
            node1.Next = this.tHead;
            this.tHead = node1;
            node1 = node2;
          }
        }
      }
    }
    #endregion
  }
  class Program
  {
    static void Main(string[] args)
    {
      /*測(cè)試單鏈表的清空
      lList.Clear();
      Node<int> n = new Node<int>();
      n = lList.Head;
      while (n != null)
      {
        Console.WriteLine(n.Data);
        n = n.Next;
      }
      Console.ReadLine();
       */
      /*測(cè)試單鏈表返回元素個(gè)數(shù)
      LinkedList<int> lList = new LinkedList<int>();
      lList.Add(3);
      Console.WriteLine(lList.GetLength());
      Console.ReadLine();
      */
      /*測(cè)試單鏈表插入
      LinkedList<int> lList = new LinkedList<int>();
      lList.Insert(0,1);
      lList.Add(1);
      lList.Add(2);
      lList.Add(3);
      lList.Add(4);
      lList.Insert(99,3);
      Node<int> n = new Node<int>();
      n = lList.Head;
      while (n != null)
      {
        Console.WriteLine(n.Data);
        n = n.Next;
      }
      Console.ReadLine();
      */
      /*測(cè)試單鏈表獲取某位置的值
      LinkedList<int> lList = new LinkedList<int>();
      lList.Add(1);
      lList.Add(2);
      lList.Add(3);
      lList.Add(4);
      Console.WriteLine(lList.GetElement(1));
      Console.ReadLine();
       */
      /*測(cè)試單鏈表刪除某位置的值
      LinkedList<int> lList = new LinkedList<int>();
      lList.Add(1);
      lList.Add(2);
      lList.Add(3);
      lList.Add(4);
      Node<int> n = new Node<int>();
      n = lList.Head;
      while (n != null)
      {
        Console.WriteLine(n.Data);
        n = n.Next;
      }
      Console.ReadLine();
      lList.Delete(2);
      Node<int> m = new Node<int>();
      m = lList.Head;
      while (m != null)
      {
        Console.WriteLine(m.Data);
        m = m.Next;
      }
      Console.ReadLine();
      */
       /*測(cè)試單鏈表按值查找元素位置
      LinkedList<int> lList = new LinkedList<int>();
      lList.Add(1);
      lList.Add(2);
      lList.Add(3);
      lList.Add(4);
      Console.WriteLine(lList.LocateElement(3));
      Console.ReadLine();
      */
      /*測(cè)試單鏈表Reverse操作（逆序）
      LinkedList<int> lList = new LinkedList<int>();
      lList.Add(1);
      lList.Add(2);
      lList.Add(3);
      lList.Add(4);
      lList.Add(5);
      Node<int> m = new Node<int>();
      m = lList.Head;
      while (m != null)
      {
        Console.WriteLine(m.Data);
        m = m.Next;
      }
      Console.ReadLine();
      lList.Reverse();
      Node<int> n = new Node<int>();
      n = lList.Head;
      while (n != null)
      {
        Console.WriteLine(n.Data);
        n = n.Next;
      }
      Console.ReadLine();
      */
      /*測(cè)試單鏈表從頭部添加元素
      LinkedList<int> lList = new LinkedList<int>();
      lList.Add(1,AddPosition.Head);
      lList.Add(2, AddPosition.Head);
      lList.Add(3, AddPosition.Head);
      lList.Add(4, AddPosition.Head);
      lList.Add(5, AddPosition.Head);
      Node<int> m = new Node<int>();
      m = lList.Head;
      while (m != null)
      {
        Console.WriteLine(m.Data);
        m = m.Next;
      }
      Console.ReadLine();
      */
      /*測(cè)試對(duì)單鏈表清除重復(fù)元素操作（返回另一鏈表）。這個(gè)例子中避免使用Add（）方法，因?yàn)槊總€(gè)Add（）都要從頭到尾進(jìn)行遍歷，不適用Add（）方法
       就要求對(duì)目標(biāo)鏈表的最后一個(gè)元素實(shí)時(shí)保存。另一種避免的方法在于從頭部Add，但這樣的最終結(jié)果為倒序
      LinkedList<int> lList = new LinkedList<int>();//原鏈表
      LinkedList<int> lList2 = new LinkedList<int>();//保存結(jié)果的鏈表
      lList.Add(1);
      lList.Add(2);
      lList.Add(1);
      lList.Add(3);
      lList.Add(3);
      lList.Add(4);
      lList.Add(5);
      Node<int> m = new Node<int>();
      m = lList.Head;
      while (m != null)
      {
        Console.WriteLine(m.Data);
        m = m.Next;
      }
      Console.ReadLine();
      Node<int> node1 = lList.Head;//標(biāo)識(shí)原鏈表的當(dāng)前要參與比較大小的元素，即可能放入鏈表2中的元素
      Node<int> node2;//標(biāo)識(shí)結(jié)果單鏈表的最后一個(gè)元素，避免使用Add函數(shù)造成多次遍歷
      Node<int> node3;//對(duì)node1的后繼進(jìn)行暫時(shí)保存，并最終付給node1
      node3 = node1.Next;
      lList2.Head = node1;//鏈表1的頭結(jié)點(diǎn)肯定要加入鏈表2
      node2 = lList2.Head;//node2表示鏈表2的最后一個(gè)元素，此時(shí)最后一個(gè)元素為頭結(jié)點(diǎn)
      node2.Next = null;//由于是把node1賦給了鏈表2的頭結(jié)點(diǎn)，必須把它的后續(xù)結(jié)點(diǎn)設(shè)為null，否則會(huì)一起帶過(guò)來(lái)
      node1 = node3;//如果沒(méi)有node3暫存node1的后繼，對(duì)lList2.Head后繼賦為null的就會(huì)同時(shí)修改node1的后繼，因?yàn)閮烧咧赶蛲粔K內(nèi)存
      while (node1 != null)
      {
        //在iList2中比較大小
        Node<int> tmp = lList2.Head;
        if (node1.Data.Equals(tmp.Data))
        {
          node1 = node1.Next;
          continue;//若相等，則node1向后移一位，重新計(jì)算
        }
        else
        {
          Node<int> tmp2 = tmp;
          tmp = tmp.Next;//tmp標(biāo)識(shí)鏈表2的用于循環(huán)的節(jié)點(diǎn)，與node比較
          if (tmp == null)//當(dāng)鏈表2中現(xiàn)有元素與node1都不相等時(shí)
          {
            node3 = node1.Next;
            node2.Next = node1;
            node2 = node1;
            node2.Next = null;
            node1 = node3;
            continue;
          }
          while (tmp != null)//tmp不為null時(shí)，一直循環(huán)到它為null
          {
            if (node1.Data.Equals(tmp.Data))
            {
              node1 = node1.Next;
            }
            else
            {
              tmp2 = tmp;
              tmp = tmp.Next;
              if (tmp == null)
              {
                node3 = node1.Next;
                node2.Next = node1;
                node2 = node1;
                node2.Next = null;
                node1 = node3;
              }
            }
          }
        }
      }
      //輸出清除重復(fù)處理后的數(shù)組
      Node<int> n = new Node<int>();
      n = lList2.Head;
      while (n!= null)
      {
        Console.WriteLine(n.Data);
        n = n.Next;
      }
      Console.ReadLine();
      */
    }
  }
}