C++ 链表实现栈、队

链表实现栈?

// 链表实现栈
#include<iostream>
using namespace std;

// 链表节点
class Node
{
public:
    int data;
    Node* next;
    Node(){}
    Node(int data):data(data),next(nullptr){}
};

// 链表栈
class ListStack
{
public:
    Node* top;
    int count;
public:
    ListStack();
    void push_stack(int data);
    void pop_stack();
    void show_stack();
};

ListStack::ListStack(){
    this->top = NULL;
    this->count = 0;
}

void ListStack::push_stack(int data){
    Node* new_node = new Node(data);
    new_node->next = this->top;
    this->top = new_node;
    this->count ++;
}

void ListStack::pop_stack(){
    if(this->count){
        Node* tmp = this->top;
        this->top = top->next;
        delete tmp;
        tmp = NULL;
        this->count --;
    }
}

void ListStack::show_stack(){
    if(this->top == NULL){
        cout<<"the stack is empty!"<<endl;
    }
    else{
        Node* cur = this->top;
        while(cur != NULL){
            cout<<cur->data<<',';
            cur = cur->next;
        }
        delete cur;
        cur = NULL;
        cout<<endl;
    }
}

int main()
{
    ListStack* mystack = new ListStack();
    mystack->show_stack();
    
    mystack->push_stack(1);
    cout<<"top= "<<mystack->top->data<<",count= "<<mystack->count<<endl;
    mystack->show_stack();
    
    mystack->push_stack(2);
    cout<<"top= "<<mystack->top->data<<",count= "<<mystack->count<<endl;
    
    mystack->show_stack();
    
    mystack->pop_stack();
    mystack->show_stack();

    return 0;
}

链表实现队列

// 链表实现队列

#include<iostream>
using namespace std;

//链表节点
class Node
{
public:
    int data;
    Node* next;
public:
    Node(){}
    Node(int data):data(data),next(nullptr){}
};

//链表队列：头部删除，尾部添加（先去先出）
class ListQueue
{
public:
    Node* front;
    Node* rear;
    int count;
public:
    ListQueue(){
        this->count = 0;
        this->front = NULL;
        this->rear = NULL;
    }
    void push_queue(int data);
    void pop_queue();
    void show_queue();
};

// 尾插 入队
void ListQueue::push_queue(int data){
    Node* new_node = new Node(data);
    if(this->rear != NULL){
        this->rear->next = new_node;
        this->rear = new_node;
    }
    else{
        this->rear = new_node;
        this->front = new_node;
    }
    this->count ++;
}

// 头部删除:出队
void ListQueue::pop_queue(){
    //队列为空
    if(this->front == NULL){
        return;
    }
    else{
        Node* tmp = this->front;
        //队列只有一个元素
        if(this->front == this->rear){
            this->front = NULL;
            this->rear = NULL;
        }
        else{
            this->front = this->front->next;
        }
        delete tmp;
        tmp = NULL;
        this->count --;
    }

}

//遍历队列
void ListQueue::show_queue(){
    if(this->front == NULL){
        cout << "the queue is empty" << endl;
    }
    else{
        Node* cur = this->front;
        while(cur != NULL){
            cout<<cur->data<<", ";
            cur = cur->next;
        }
        cout<<endl;
        cout<<"count:"<<this->count<<endl;
    }
}

int main()
{
    ListQueue* myqueue = new ListQueue();
    myqueue->show_queue();
    
    myqueue->push_queue(1);
    myqueue->push_queue(2);
    myqueue->push_queue(3);
    cout<<"front:"<<myqueue->front->data<<", rear:"<<myqueue->rear->data<<endl;
    
    myqueue->show_queue();
    
    myqueue->pop_queue();
    myqueue->show_queue();

    return 0;
}