双向链表的操作

2013-08-17 17:57:12

双向链表的操作。

代码（测试通过，暂未发现错误，欢迎交流指正！）：

#include <iostream>
#include <cassert>
using namespace std;

typedef int DataType;  //链表元素类型

typedef struct doubleLinkNode    //双向链表结点
{
    DataType data;
    doubleLinkNode *prior;
    doubleLinkNode *next;
}DLNode,*PDLNode;

//链表初始化
void InitDoubleLink(PDLNode &pHead)
{
    pHead = new DLNode;
    pHead->data = 0;
    pHead->prior = NULL;
    pHead->next = NULL;
}

//创建链表
PDLNode CreatDoubleLink(PDLNode &pHead)
{
    DataType dataTmp = 0;
    PDLNode pNew = NULL;
    //PDLNode pPre = pHead;

    InitDoubleLink(pHead);
    PDLNode pPre = pHead;  //在InitDoubleLink之后赋值，而不是在之前赋值

    cout<<"Please enter the elements of the link  ,separate with space,and end with ctrl+z :"<<endl;
    while (cin>>dataTmp)
    {
        pNew = new DLNode;  //new出来的空间需要测试是否为空吗？
        pNew->data = dataTmp;
        pNew->next = NULL;
        pNew->prior = pPre;

        pPre->next = pNew;
        pPre = pNew;
    }

    return pHead;
}

//删除链表元素
PDLNode DeleteDoubleLink(PDLNode &pHead,size_t posToDelete)
{
    assert(NULL != pHead);

    PDLNode pCur = pHead;
    while (posToDelete--)  
    {
        pCur = pCur->next;
        assert(NULL != pCur);
    }

    pCur->prior->next = pCur->next;
    if (pCur->next != NULL)
    {
        pCur->next->prior = pCur->prior;
    }

    delete pCur;
    return pHead;
}

//链表插入
PDLNode InsertDoubleLink(PDLNode &pHead,size_t posToInsert,const DataType dataToInsert)
{
    assert(NULL != pHead);

    PDLNode pNew = new DLNode;  //new出来的空间需要测试是否为空吗？
    pNew->data = dataToInsert;
    pNew->next = NULL;
    pNew->prior = NULL;

    PDLNode pCur = pHead;
    while (posToInsert--)  
    {
        pCur = pCur->next;
        assert(NULL != pCur);
    }

    pNew->prior = pCur;
    pNew->next = pCur->next;
    pCur->next = pNew;

    if (pCur->next != NULL)   //对插入到尾部的情况进行处理
    {
        pCur->next->prior = pNew;
    }

    return pHead;
}

//链表显示
void DisplayDoubleLink(const PDLNode &pHead)
{
    assert(NULL != pHead);
    PDLNode pCur = pHead->next;

    while (NULL != pCur)
    {
        cout<<pCur->data<<"	";
        pCur = pCur->next;
    }
    cout<<endl;
}

//链表销毁
void DestoryDoubleLink(PDLNode &pHead)
{
    assert(NULL != pHead);
    PDLNode pCur = pHead->next;
    
    while (NULL != pCur)
    {
        delete pCur->prior;
        pCur = pCur->next;
    }
}

//链表测试
void TestDoubleLink()
{
    PDLNode pHead = NULL;

    //Test CreatDoubleLink...
    cout<<"Test CreatDoubleLink..."<<endl;
    pHead = CreatDoubleLink(pHead);
    cout<<"display the link created by CreatLink : "<<endl;
    DisplayDoubleLink(pHead);
    cin.clear();  //清除流状态
    cin.sync();
    

    //Test InsertDoubleLink...
    //cout<<"Test InsertDoubleLink..."<<endl;
    //size_t posToInsert = 0;
    //DataType dataToInsert = 0;

    //cout<<"Please enter the position and the data to insert,end with ctrl+z :"<<endl;
    //while (cin>>posToInsert>>dataToInsert)
    //{
    //    cout<<"The link before insertion : "<<endl;
    //    DisplayDoubleLink(pHead);

    //    pHead = InsertDoubleLink(pHead,posToInsert,dataToInsert);

    //    cout<<"The link after insertion : "<<endl;
    //    DisplayDoubleLink(pHead);

    //    cout<<"Please enter the position to insert,end with ctrl+z :"<<endl;
    //}
    //cin.clear();  //清除流状态
    //cin.sync();

    //Test DeleteDoubleLink...
    size_t posToDelete = 0;
    
    cout<<"Please enter the position to delete,end with ctrl+z :"<<endl;
    while (cin>>posToDelete)
    {
        cout<<"The link before insertion : "<<endl;
        DisplayDoubleLink(pHead);

        pHead = DeleteDoubleLink(pHead,posToDelete);

        cout<<"The link after delete : "<<endl;
        DisplayDoubleLink(pHead);

        cout<<"Please enter the position to delete,end with ctrl+z :"<<endl;
    }

    cin.clear();  //清除流状态
    cin.sync();

    DestoryDoubleLink(pHead);
}

//main
int main()
{
    TestDoubleLink();
    return 0;
}