C++单链表类(带头结点)

Link.h

#ifndef _LINK_0411
#define _LINK_0411
#include <string>
#include <iostream>
//定义数据类型为整型 
typedef int ElementType; 
//定义结点 
struct Node
{ 
    ElementType data; 
    Node * next;
};
//带头结点链表 
class Link 
{ 
public: 
    Link(); 
    ~Link(); 
    //选择排序 
    void select_sort(); 
    //冒泡排序 
    void bubble_sort(); 
    //头部插入 
    void insert_head(ElementType data); 
    //尾部插入 
    void insert_tail(ElementType data); 
    //查找结点,返回序号，如果不存在返回-1 
    int find(ElementType data); 
    //删除结点 
    bool delete_node(int pos); 
    //逆置 
    void reverse(); 
    //打印链表 
    void display(); 
    //打印提示信息 
    void printhelp(); 
    //返回长度
    int size(); 
private: 
    //头结点指针 
    Node * pHead; 
    //链表长度 
    size_t iSize; 
}; 
#endif

Link.cpp

#include "Link.h"

Link::Link():pHead(NULL), iSize(0)
{
    pHead = new Node;
    pHead->next = NULL;
}

Link::~Link()
{
    Node * tmpNode = NULL;
    Node * p = pHead->next;
    while (p != NULL)
    {
        tmpNode = p->next;
        delete p;
        p = tmpNode;
    }
    delete tmpNode;
    tmpNode = NULL;

    delete pHead;
    p = NULL;

    iSize = 0;
}

/**********************************
   链表选择排序(递增)
***********************************/
void Link::select_sort()
{
    Node * p , *q;
    int temp;

    for (p = pHead; p != NULL; p = p->next)
        for (q = p->next; q != NULL; q = q->next)
        {
            if (p->data > q->data)
            {
                temp = p->data;
                p->data = q->data;
                q->data = temp;
            }
        }
}

/**********************************
   链表冒泡排序(递增)
***********************************/
void Link::bubble_sort()
{
    Node *p;
    int temp;

    /************************************************************************/
    /*       冒泡排序是每次从头开始比较相邻的两个数，大小相反则交换，结束的 */
    /*        条件是这一轮中没有发生交换，flag用来记录是否发生了交换          */
    /************************************************************************/
    int flag;
    while (true)
    {
        flag = 0;
        for (p = pHead; p->next != NULL; p = p->next)
        {
            if (p->data > p->next->data)
            {
                temp = p->data;
                p->data = p->next->data;
                p->next->data = temp;
                flag = 1;
            }
        }
        if (flag == 0)
            break;
    }
}

/********************************
   链表头部插入
*****************************/
void Link::insert_head(ElementType data)
{
    Node * tmpNode = new Node;
    tmpNode->data = data;
    
    tmpNode->next = pHead->next;
    pHead->next = tmpNode;
    
    iSize++;

    tmpNode = NULL;
}

/********************************
   链表尾部插入
*****************************/
void Link::insert_tail(ElementType data)
{
    Node * tmpNode = new Node;
    tmpNode->data = data;
    tmpNode->next = NULL;

    Node * p = NULL;
    p = pHead;
    while (p->next != NULL)
    {
        p = p->next;
    }

    p->next = tmpNode;
    iSize++;

    //delete tmpNode;
    tmpNode = NULL;
    //delete p;
    p = NULL;
}

/********************************
   打印链表
*****************************/
void Link::display()
{
    int count = 1;
    Node * tmpNode = NULL;

    tmpNode = pHead->next;
    while (tmpNode != NULL)
    {
        std::cout<<tmpNode->data<<" ";
        tmpNode = tmpNode->next;

        /********************************
        *  输出格式控制，每行10个
        **********************************/
        if (count % 10 == 0)
        {
            std::cout<<std::endl;
        }
        count++;
    }
    std::cout<<std::endl;
    tmpNode = NULL;
}

/********************************
   查找结点
*****************************/
int Link::find(ElementType data)
{
    int pos = 0;
    Node * tmpNode = NULL;

    tmpNode = pHead->next;
    while (tmpNode != NULL)
    {
        if ( tmpNode->data == data)
        {
            return pos;
        }
        tmpNode = tmpNode->next;
        pos++;
    }

    tmpNode = NULL;
    return -1;
}

/********************************
   删除结点
*****************************/
bool Link::delete_node(int pos)
{
    //序号超过链表范围则报错退出
    if (pos > iSize -1)
    {
        return false;
    }
    else
    {
        int k = 0;
        Node * tmpNode = NULL;
        tmpNode = pHead;
        while ( k < pos)
        {
            tmpNode = tmpNode->next;
            k++;
        }
        Node * p = NULL;
        p = tmpNode->next;

        tmpNode->next = tmpNode->next->next;
        delete p;
        p = NULL;
        iSize--;
        return true;
    }
}

/********************************
   返回链表的长度
*****************************/
int Link::size()
{
    return iSize;
}

/********************************
   链表的逆置
*****************************/
void Link::reverse()
{
    Node * preNode = NULL;
    Node * curNode = NULL;
    Node * afterNode = NULL;

    if ( iSize == 1 || iSize == 0)
    {
        return;
    }
    else if ( iSize >= 2)
    {
        preNode = pHead->next;
        curNode = preNode->next;
        afterNode = curNode->next;

        preNode->next = NULL;
        
        while (afterNode != NULL)
        {
            curNode->next = preNode;

            preNode = curNode;
            curNode = afterNode;

            afterNode = afterNode->next;
        }

        /********************************************************************
        * 将当前结点的next置为前一个结点的过程是在每一次循环的开始，而最后一次
        * 循环后无法进入下一次循环，需要补一次设置curNode的next的过程
        *********************************************************************/
        curNode->next = preNode;

        pHead->next = curNode;
    }
    preNode = NULL;
    curNode = NULL;
    afterNode = NULL;
}

void Link::printhelp()
{
    std::cout<<"*****************************************
";
    std::cout<<"当前链表为:"<<std::endl;
    if (iSize == 0)
        std::cout<<"NULL"<<std::endl;
    else
        display();
    std::cout<<"输入你的选择:
"
        "0.从头部插入结点
"
        "1.从尾部插入结点
"
        "2.逆置链表
"
        "3.打印链表
"
        "4.删除结点
"
        "5.输出链表长度
"
        "6.查找结点
"
        "7.选择排序
"
        "8.冒泡排序
"
        "9.退出"<<std::endl;
    std::cout<<"*****************************************
";
}

main函数

// linklist.cpp : 定义控制台应用程序的入口点。
//

#include "Link.h"

int main(int argc, char * argv[])
{
    Link myLink;
    int pos;
    char choice;
    ElementType find_num = 3;
    int delchoice;

    for (int i = 0 ; i < 48; i ++)
    {
        myLink.insert_head(rand()%100);
    }

    myLink.printhelp();
    std::cout<<"请选择:";
    while ( std::cin>> choice)
    {
        switch(choice)
        {
        case '0':
        case '1':
            std::cout<<"
暂无此功能!
";
            break;
        case '2':
            myLink.reverse();
            std::cout<<"
逆置成功!
";
            break;
        case '3':
            myLink.display();
            std::cout<<"
打印成功!
";
            break;
        case '4':
            std::cout<<"
输入要删除的节点序号:";
            std::cin>>delchoice;
            if (myLink.delete_node(delchoice) == true)
            {
                std::cout<<"
删除成功!
";
            }
            else 
            {
                std::cout<<"
删除失败!
";
            }
            break;
        case '5':
            std::cout<<"链表长为:"<<myLink.size()<<std::endl;
            break;
        case '6':
            goto exit;
            break;
        case '7':
            myLink.select_sort();
            break;
        case '8':
            myLink.bubble_sort();
            break;
        case '9':
            goto exit;
            break;
        default:
            break;
        }
        myLink.printhelp();
        std::cout<<"请选择:";
    }

exit:    
    system("pause");
    return 0;
}

 运行：