数据结构---链表ADT C++实现

最近在学习数据结构，刚开始一直在看书，但是总是感觉似懂非懂，心想还不如自己操练一波，势必有所收获。现将实现代码发表此地，以备日后复习，若有错误或者建议，欢迎告知本人！

1. 节点类

 class Node {
 public:
     int data;
     Node *next;
     Node(int da):
         data(da), next(NULL){}
 };

这里节点类的定义采用多数OJ的模版（当然，也可以使用 struct ）

2. 链表类ADT

 class List{
 private:
     Node *head;
 public:
     List(): head(NULL){}
     ~List(){
         delete head;
         cout<<"The list is deleted."<<endl;
     };
     int size(); // 链表长度
     bool isEmpty(); // 是否为空
     void printList(); // 打印链表
     void insert(int position, int value); // 指定位置插入
     void insertHead(int value); // 插入到最前
     void insertTail(int value); // 插入到最后
     int getValue(int position); // 查找指定位置的值
     int search(int value); // 查找指定元素的位置
     void update(int position, int value); // 更新指定位置的值
     int erase(int position); // 删除指定位置的节点
     void reverse(); // 反转链表
     //void clearList() // 清空链表
 };

3. 完整代码

 #include<iostream>
 using namespace std;

 class Node {
 public:
     int data;
     Node *next;
     Node(int da):
         data(da), next(NULL){}
 };

 class List{
 private:
     Node *head;
 public:
     List(): head(NULL){}
     ~List(){
         delete head;
         cout<<"The list is deleted."<<endl;
     };
     int size(); // 链表长度
     bool isEmpty(); // 是否为空
     void printList(); // 打印链表
     void insert(int position, int value); // 指定位置插入
     void insertHead(int value); // 插入到最前
     void insertTail(int value); // 插入到最后
     int getValue(int position); // 查找指定位置的值
     int search(int value); // 查找指定元素的位置
     void update(int position, int value); // 更新指定位置的值
     int erase(int position); // 删除指定位置的节点
     void reverse(); // 反转链表
     //void clearList() // 清空链表
 };

 // 返回链表大小
 int List::size(){
     Node *p = head;
     int index = ;
     while(p != NULL){
         index++;
         p = p->next;
     }
     return index;
 }

 // 判断链表是否为空
 bool List::isEmpty(){
     if(List::size() == )
         return true;
     else
         return false;
 }

 // 打印链表
 void List::printList(){
     Node *p = head;
     while(p != NULL){
         cout<<p->data<<" ";
         p = p->next;
     }
     cout<<endl;
     cout<<endl;
 }

 // 在position位置插入value
 void List::insert(int position, int value){
     if(position< || position>List::size()){
         cout<<"position error, please check."<<endl;
         return ;
     }
     Node *s = new Node(value); // new node
     Node *p = head;
     if(head == NULL){ // isEmpty = true
         head = s;
     }
     else{ // isEmpty = false
         if(position == ){
             s->next = p;
             head = s;
         }
         else{
             int index = ;
             while(index != position-){
                 p = p->next;
                 index++;
             }
             s->next = p->next;
             p->next = s;
         }
     }
     if (position == )
         cout<<"insert "<<value<<" at the first."<<endl;
     else if (position == List::size())
         cout<<"insert "<<value<<" at the tail."<<endl;
     else
         cout<<"insert "<<value<<" at position "<<position<<endl;
 }

 // 头部插入
 void List::insertHead(int value){
     List::insert(, value);
 }

 // 尾部插入
 void List::insertTail(int value){
     List::insert(List::size(), value);
 }

 // 搜索数据value，并返回位置
 int List::search(int value){
     Node *p = head;
     int index = ;
     while(p != NULL && p->data != value){
         index++;
         p = p->next;
     }
     if(p == NULL){
         cout<<"the value is not in the list, please check."<<endl;
         return -;
     }
     else{
         cout<<value<<" at position "<<index<<endl;
         return index;
     }
 }

 // 将position位置的数据更新为value
 void List::update(int position, int value){
     if(position< || position>(List::size()-)){
         cout<<"position error, please check."<<endl;
         return ;
     }
     Node *p = head;
     int index = ;
     while(index != position){
         p = p->next;
         index++;
     }
     p->data = value;
     cout<<"update "<<value<<" at position "<<position<<endl;
 }

 // 删除position位置的数据，并返回
 int List::erase(int position){
     if(position< || position>(List::size()-)){
         cout<<"position error, please check."<<endl;
         return -;
     }
     int res = List::getValue(position);
     Node *p = head;
     int index = ;
     cout<<"erase data at position "<<position<<endl;
     if(position == ){
         head = p->next;
         return res;
     }
     else{
         while(index != position-){
             p = p->next;
             index++;
         }
         Node *temp = p->next;
         p->next = temp->next;
         return res;
     }
 }

 // 反转链表
 void List::reverse(){
     if (head == NULL || head->next == NULL)
         return ;
     Node *prev = head;
     Node *cur = head->next;
     Node *temp = head->next->next;
     while(cur){
         temp = cur->next;
         cur->next = prev;
         prev = cur;
         cur = temp;
     }
     head->next = NULL; // 更新末尾元素的指针
     head = prev; // 更新头结点
     cout<<"reverse the list."<<endl;
 }

 // 返回position位置的数据
 int List::getValue(int position){
     if(position< || position>(List::size()-)){
         cout<<"position error, please check."<<endl;
         return -;
     }
     Node *p = head;
     int index = ;
     while(index != position){
         p = p->next;
         index++;
     }
     cout<<"position "<<position<<" is "<<p->data<<endl;
     return p->data;
 }
 /*
 void List::clearList(){
     Node *p = head;
     while(p){
         Node *temp = p->next;
         delete p;
         p = temp;
     }
 }
 */
 int main() {
     List l1;
     l1.insertTail();l1.printList();
     l1.insertHead();l1.printList();
     l1.insert(, );l1.printList();
     l1.insert(, );l1.printList();
     l1.insert(, );l1.printList();
     l1.insert(, );l1.printList();
     l1.insert(, );l1.printList();
     l1.search();
     l1.getValue();
     l1.update(, );l1.printList();
     l1.erase();l1.printList();
     l1.reverse(); l1.printList();
     cout<<"The size of the list: "<<l1.size()<<endl;
     return ;
 }

4. 运行结果

insert  at the first.

insert  at the first.

insert  at position 

insert  at the first.

insert  at position 

insert  at the first.

insert  at position 

 at position
position  is
update  at position 

position  is
erase data at position 

reverse the list.

The size of the list:
The list is deleted.
[Finished in .0s]

关于每一部分的详解会继续补充。