一：介绍
线性表是最基本，最简单也是应用最广的数据结构。线性表是线性数据的抽象，其特点是结构中的数据元素之间存在着一对一的线性关系，
是一种数据元素序列的数据结构。
线性表是由n>=0个相同的数据元素构成的有限序列，有限指的是线性表中的数据元素个数是有限的，并且每一个数据元素都有自己的位置。
二：代码实现
1. 线性表的一些通用操作，我们统一为接口：
public interface IListDS<T>
{
int GetLength();
void Clear();
bool IsEmpty();
void Append(T item);
void Insert(T item, int i);
T Delete(int i);
T GetElem(int i);
int Locate(T value);
void Reverse();
}
2. 线性表中常见的有顺序表，单链表，双向链表，循环链表。
3. 顺序表
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace SeqDS
{
public class SeqList<T>:IListDS<T>
{
private int maxsize;//顺序表的容量
private T[] data;//数组，用于存储顺序表中的数据元素
private int last;//指示顺序表最后一个元素的位置
//索引器
public T this[int index]
{
get { return data[index]; }
set { data[index] = value; }
}
public int Last
{
get { return last; }
}
public int Maxsize
{
get{return maxsize;}
set { maxsize = value; }
}
//构造器
public SeqList(int size)
{
data = new T[size];
maxsize = size;
last = -1;
}
//求顺序表的长度
public int GetLength()
{
return last + 1;
}
//清空顺序表
public void Clear()
{
last = -1;
}
//判断顺序表是否为空
public bool IsEmpty()
{
if (last == -1)
return true;
else
return false;
}
//判断顺序表是否为满
public bool IsFull()
{
if (last == maxsize - 1)
return true;
else
return false;
}
//在顺序表的末尾添加新元素
public void Append(T item)
{
if (IsFull())
{
Console.WriteLine("List is full");
return;
}
data[++last] = item;
}
//在顺序表的第i个数据元素的位置插入一个数据元素
public void Insert(T item, int i)
{
if (IsFull())
{
Console.WriteLine("List is full");
return;
}
if (i < 1 || i > last + 2)
{
Console.WriteLine("Position is error!");
return;
}
if (i == last + 2)
{
data[last + 1] = item;
}
else
{
for (int j = last; j > i - 1; --j)
{
data[j + 1] = data[j];
}
data[i - 1] = item;
}
++last;
}
//删除顺序表的第i个数据元素
public T Delete(int i)
{
T tmp = default(T);
if (IsEmpty())
{
Console.WriteLine("List is empty!");
return tmp;
}
if (i < 1 || i > last + 1)
{
Console.WriteLine("Position is error!");
return tmp;
}
if (i == last + 1)
{
tmp = data[last--];
}
else
{
tmp = data[i - 1];
for (int j = i; j <= last; ++j)
{
data[j] = data[j + 1];
}
}
--last;
return tmp;
}
//获得顺序表的第i个数据元素
public T GetElem(int i)
{
if (IsEmpty() || (i < 1) || (i > last + 1))
{
Console.WriteLine("List is empty or Position is erroe!");
return default(T);
}
return data[i - 1];
}
//在顺序表中查找值为value的数据元素
public int Locate(T value)
{
if (IsEmpty())
{
Console.WriteLine("List is Empty!");
return -1;
}
int i = 0;
for (i = 0; i <= last; ++i)
{
if (value.Equals(data[i]))
break;
}
if (i > last)
return -1;
return i;
}
public void Reverse()
{
T tmp = default(T);
int length = GetLength();
for (var i = 0; i < length / 2; i++)
{
tmp = data[i];
data[i] = data[length - i - 1];
data[length - i - 1] = tmp;
}
}
}
}
4. 单向链表
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace SeqDS
{
public class LinkList<T>:IListDS<T>
{
private Node<T> head;
public Node<T> Head
{
get { return head; }
set { head = value; }
}
public LinkList()
{
head = null;
}
public int GetLength()
{
Node<T> p = head;
int len = 0;
while (p != null)
{
++len;
p = p.Next;
}
return len;
}
public bool IsEmpty()
{
if (head == null)
return true;
else
return false;
}
public void Clear()
{
head = null;
}
public void Append(T item)
{
Node<T> q = new Node<T>(item);
Node<T> p=new Node<T>();
if(head==null)
{
head=p;
return;
}
p=head;
while(p.Next!=null)
{
p=p.Next;
}
p.Next=q;
}
public void Insert(T item, int i)
{
if(IsEmpty()||i<1)
{
Console.WriteLine("List is empty or Position is error");
return;
}
if (i == 1)
{
Node<T> q = new Node<T>(item);
q.Next = head;
head = q;
return;
}
Node<T> p = head;
Node<T> r = new Node<T>();
int j = 1;
while (p.Next != null && j < i)
{
r = p;
p = p.Next;
++j;
}
if (j == i)
{
Node<T> q = new Node<T>(item);
q.Next = p;
r.Next = q;
}
}
public void InsertPost(T item, int i)
{
if (IsEmpty() || i < 1)
{
Console.WriteLine("List is empty or Position is error");
return;
}
if (i == 1)
{
Node<T> q = new Node<T>(item);
q.Next = head.Next;
head.Next = q;
return;
}
Node<T> p = head;
int j = 1;
while (p != null && j < i)
{
p = p.Next;
++j;
}
if (j == i)
{
Node<T> q = new Node<T>(item);
q.Next = p.Next;
p.Next = q;
}
}
public T Delete(int i)
{
if (IsEmpty() || i < 0)
{
Console.WriteLine("Link is empty or Positon is error");
return default(T);
}
Node<T> q = new Node<T>();
if (i == 1)
{
q = head;
head = head.Next;
return q.Data;
}
Node<T> p = head;
int j = 1;
while (p.Next != null && j < i)
{
++j;
q = p;
p = p.Next;
}
if (j == i)
{
q.Next = p.Next;
return p.Data;
}
else
{
Console.WriteLine("The ith node is not exist!");
return default(T);
}
}
public T GetElem(int i)
{
if (IsEmpty())
{
Console.WriteLine("List is empty");
return default(T);
}
Node<T> p = new Node<T>();
p = head;
int j = 1;
while (p.Next != null && j < i)
{
++j;
p = p.Next;
}
if (j == i)
{
return p.Data;
}
else
{
Console.WriteLine("the ith node is not exist!");
return default(T);
}
}
public int Locate(T value)
{
if (IsEmpty())
{
Console.WriteLine("List is Empty");
return -1;
}
Node<T> p = new Node<T>();
p = head;
int i = 1;
while (!p.Data.Equals(value) && p.Next != null)
{
p = p.Next; ;
++i;
}
return i;
}
public void Reverse()
{
Node<T> p = head.Next;
Node<T> q = new Node<T>();
head.Next = null;
while (p != null)
{
q = p;
p = p.Next;
q.Next = head.Next;
head.Next = q;
}
}
}
public class Node<T>
{
private T data;//数据域
private Node<T> next;//引用域
public Node(T val, Node<T> p)
{
data = val;
next = p;
}
public Node(Node<T> p)
{
next=p;
}
public Node(T val)
{
data = val;
next = null;
}
public Node()
{
data = default(T);
next = null;
}
public T Data
{
get { return data; }
set { data = value; }
}
public Node<T> Next
{
get { return next; }
set { next = value; }
}
}
}
下面实现两个创建链表的函数如下：
//在头部插入结点建立单链表
static LinkList<int> CreateListHead()
{
int d;
LinkList<int> l = new LinkList<int>();
d = Int32.Parse(Console.ReadLine());
while (d != -1)
{
Node<int> p = new Node<int>(d);
p.Next = l.Head;
l.Head = p;
d = Int32.Parse(Console.ReadLine());
}
return l;
}
//在尾部插入节点建立单链表
static LinkList<int> CreateListTail()
{
Node<int> r = new Node<int>();
int d;
LinkList<int> l = new LinkList<int>();
r = l.Head;
d = Int32.Parse(Console.ReadLine());
while (d != -1)
{
Node<int> p = new Node<int>(d);
if (l.Head == null)
{
l.Head = p;
}
else
{
r.Next = p;
}
r = p;
d = Int32.Parse(Console.ReadLine());
}
if (r != null)
{
r.Next = null;
}
return l;
}
5. 双向链表
5.1.双向链表的结点实现如下：
public class DbNode<T>
{
private T data;
private DbNode<T> prev;
private DbNode<T> next;
public DbNode(T val, DbNode<T> p)
{
data = val;
next = p;
}
public DbNode(DbNode<T> p)
{
next = p;
}
public DbNode(T val)
{
data = val;
next = null;
}
public DbNode()
{
data = default(T);
next = null;
}
public T Data
{
get { return data; }
set { data = value; }
}
public DbNode<T> Prev
{
get { return prev; }
set { prev = value; }
}
public DbNode<T> Next
{
get { return next; }
set { next = value; }
}
}
5.2. 插入
由于双向链表的结点有两个引用，所以在双向链表中插入和删除结点比单链表要复杂，双向链表中结点的插入也分前插和后插，例如：设p指向某一结点，即p存储的是结点的地址，现将s插入到p前面，插入过程如下图：
对应的操作如下：
p.Next.Prev=s;
s.Prev=p;
s.Next=p.Next;
p.Next=s;
5.3.删除
我们以删除p结点的后面的结点为例，删除过程如下：
操作如下：
p.Next=p.Next.Next;
P.Next.Prev=p.Prev;
双向链表的其他操作与单链表相似。
