C++ 链表

 1 #pragma once
 2 
 3 //节点结构体
 4 template<class T>
 5 struct Node
 6 {
 7     T value;
 8     Node<T> *next;
 9 };
10 
11 template<class T>
12 class LinkList
13 {
14 private:
15     unsigned count;                 //节点个数
16     Node<T> *head;                  //表头指针
17     Node<T> *tail;                  //表尾指针
18 public:
19     LinkList();                     //构造函数
20     ~LinkList();                    //析构函数
21     unsigned length();              //返回链表长度
22     T first();                      //返回第一个节点值
23     T last();                       //返回最后一个节点值
24     void addNode(T);                //添加节点
25     void insert(T, unsigned);       //在指定位置之后插入
26     void insert_before_head(T);     //在头节点之前插入
27     void remove(unsigned);          //移除指定位置的节点
28     void print_all();               //输出所有节点
29 };

  1 #include "LinkList.h"
  2 #include <iostream>
  3 
  4 //构造函数
  5 template<class T>
  6 LinkList<T>::LinkList()
  7 {
  8     head = NULL;
  9     tail = NULL;
 10     count = 0;
 11 }
 12 
 13 //析构函数
 14 template<class T>
 15 LinkList<T>::~LinkList()
 16 {
 17     Node<T> *cur;
 18     while (head != NULL)
 19     {
 20         cur = head->next;
 21         delete head;
 22         head = cur;
 23     }
 24     count = 0;
 25 }
 26 
 27 //返回链表长度
 28 template<class T>
 29 unsigned LinkList<T>::length()
 30 {
 31     return count;
 32 }
 33 
 34 //返回第一个节点值
 35 template<class T>
 36 T LinkList<T>::first()
 37 {
 38     return head->value;
 39 }
 40 
 41 //返回最后一个节点值
 42 template<class T>
 43 T LinkList<T>::last()
 44 {
 45     return tail->value;
 46 }
 47 
 48 //添加节点
 49 template<class T>
 50 void LinkList<T>::addNode(T value)
 51 {
 52     Node<T> *node = new Node<T>;
 53     node->value = value;
 54     node->next = NULL;
 55     if (count == 0)
 56     {
 57         head = node;
 58         tail = node;
 59     }
 60     else
 61     {
 62         tail->next = node;
 63         tail = node;
 64     }
 65     count++;
 66 }
 67 
 68 //在指定位置之后插入
 69 template<class T>
 70 void LinkList<T>::insert(T value, unsigned index)
 71 {
 72     if (index < 1 || index > count)
 73     {
 74         std::cout << "index error!\n";
 75         return;
 76     }
 77     Node<T> *node = new Node<T>;
 78     node->value = value;
 79     //如果是最后一个节点
 80     if (index == count)
 81     {
 82         node->next = NULL;
 83         tail->next = node;
 84         tail = node;
 85     }
 86     else
 87     {
 88         Node<T> *cur = head;
 89         while (--index)
 90         {
 91             cur = cur->next;
 92         }
 93         node->next = cur->next;
 94         cur->next = node;
 95     }
 96     count++;
 97 }
 98 
 99 //在头节点之前插入
100 template<class T>
101 void LinkList<T>::insert_before_head(T value)
102 {
103     Node<T> *node = new Node<T>;
104     node->value = value;
105     node->next = head;
106     head = node;
107     count++;
108 }
109 
110 //移除指定位置的节点
111 template<class T>
112 void LinkList<T>::remove(unsigned index)
113 {
114     if (index < 1 || index > count)
115     {
116         std::cout << "index error!\n";
117         return;
118     }
119     Node<T> *cur = head;
120     if (index == 1)
121     {
122         head = cur->next;
123         delete cur;
124     }
125     else
126     {
127         int i = index;
128         while (--i > 1)
129         {
130             cur = cur->next;
131         }
132         if (index == count)
133         {
134             delete cur->next;
135             cur->next = NULL;
136         }
137         else
138         {
139             Node<T> *temp = cur->next->next;
140             delete cur->next;
141             cur->next = temp;
142         }
143     }
144     count--;
145 }
146 
147 //输出所有节点
148 template<class T>
149 void LinkList<T>::print_all()
150 {
151     Node<T> *cur = head;
152     while (cur != NULL)
153     {
154         std::cout << cur->value << " ";
155         cur = cur->next;
156     }
157 }