C++ 数据结构 双链表(模板类)

#ifndef DLIST_H_INCLUDED#define DLIST_H_INCLUDED#include<iostream>using namespace std;template<class Type>class DList;template<class Type>class ListNode{    friend class DList<Type>;public:    ListNode():data(Type()),next(NULL),prior(NULL)    {}    ListNode(Type d,ListNode<Type> *n = NULL,ListNode<Type> *m = NULL):data(d),next(n),prior(m)    {}    ~ListNode()    {}public:    void SetData(Type d)    {data = d;}    void GetData()const    {return data;}private:    Type data;    ListNode<Type> *next;    ListNode<Type> *prior;};template<class Type>class DList{public:    DList()    {        first = last = BuyNode();    }    ~DList()    {        DList<Type>::destroy();    }public:void push_back(const Type &x);void push_front(const Type &x);void show_list()const;void pop_back();void pop_front();void insert_val(const Type &x);void delete_val(const Type &x);bool find(const Type &x);Type length();void clear();void destroy();                        //摧毁该顺序表void reserv();                         //反转void sort();protected:    ListNode<Type>* BuyNode(Type x = Type()){        ListNode<Type> *p = new ListNode<Type>(x);        return p;}private:    ListNode<Type> *first;ListNode<Type> *last;};template<class Type>void DList<Type>::push_back(const Type &x){    ListNode<Type> *s = BuyNode(x);    last->next = s;    s->prior = last;    last = s;    first->data++;}template<class Type>void DList<Type>::push_front(const Type &x){    ListNode<Type> *s = BuyNode(x);    if(first == last)    {        s->prior = first;        first->next = s;        last = s;    }    else    {        first->next->prior = s;        s->prior = first;        s->next = first->next;        first->next = s;    }    first->data++;}template<class Type>void DList<Type>::show_list()const{    ListNode<Type> *p = first->next;    while(p != NULL)    {        cout<<p->data<<" ";        p = p->next;    }    cout<<endl;}template<class Type>void DList<Type>::pop_back(){    if(first->data == 0)        return;    ListNode<Type> *p = first;    while(p->next != last)        p = p->next;    ListNode<Type> *q = p->next;    p->next = NULL;    last = p;    delete q;    first->data--;}template<class Type>void DList<Type>::pop_front(){    if(first->data <= 1)        pop_back();    else    {        ListNode<Type> *p = first->next;        p->next->prior = first;        first = p->next->prior;        first->next = p->next;        p = NULL;        delete p;        first->data--;    }}template<class Type>void DList<Type>::insert_val(const Type &x){    ListNode<Type> *s =  BuyNode(x);    ListNode<Type> *p =  first->next;    if(p->data > s->data)    {        push_front(s->data);    }    else if(last->data < s->data)    {        push_back(s->data);    }    else        {            while(p != NULL)           {                if(p->next->data>x)                {                    p->next->prior = s;                    s->prior = p;                    s->next = p->next;                    p->next = s;                    first->data++;                    return;                }                p=p->next;            }        }}template<class Type>void DList<Type>::delete_val(const Type &x){    ListNode<Type> *p = first;    while (p->next != NULL && p->next->data != x)        p = p->next;    if (p->next == NULL)//未找到即返回    {        cout<<"未找到该值"<<endl;        return;    }    ListNode<Type> *q = p->next;    if (q == last)        pop_back();    else    {        q->next->prior = p;        p->next = q->next;    }    delete q;    first->data--;}template<class Type>bool DList<Type>::find(const Type &x){    ListNode<Type> *p = first->next;    while(p != NULL && p->data != x)        p = p->next;    if(p == NULL)        {cout<<"未找到该值"<<endl;        return false;}    else        {cout<<"存在该值"<<endl;        return true;}}template<class Type>Type DList<Type>::length(){    cout<<"length = "<<first->data<<endl;}template<class Type>void DList<Type>::clear(){    while(first->data >0)        pop_front();}template<class Type>void DList<Type>::destroy()//摧毁该顺序表{    clear();    first = last = NULL;    delete first;}template<class Type>void DList<Type>::reserv() //反转{    ListNode<Type> *p = first->next;    ListNode<Type> *curr = p->next;    ListNode<Type> *tmp = NULL;    first->next->next = NULL;    while (curr)   //将直接后继指向当前指针的next    {        tmp = curr->next;        curr->next = p;        p = curr;        curr = tmp;    }    first->next = p;}template<class Type>void DList<Type>::sort(){    ListNode<Type> *s = first->next;    while (s->next)    {        ListNode<Type> *p = s;        while(p->next)        {             if(s->data > p->next->data)                {                    Type tmp = s->data;                    s->data = p->next->data;                    p->next->data = tmp;                }                p = p->next;        }        s = s->next;    }}#endif // DLIST_H_INCLUDED

<pre name="code" class="cpp">#include"DList.h"int main(){    DList<int> mylist;int select = 1;int Item;int pos;while(select){cout<<"**************************************"<<endl;cout<<"* [1] push_back       [2] push_front *"<<endl;cout<<"* [3] show_list       [0] quit_system*"<<endl;cout<<"* [4] pop_back        [5] pop_front  *"<<endl;cout<<"* [6] insert_val      [7] delete_val *"<<endl;cout<<"* [8] find            [9] length     *"<<endl;cout<<"* [10]clear           [11]destroy    *"<<endl;cout<<"* [12]reserv          [13]sort       *"<<endl;cout<<"**************************************"<<endl;cout<<"请选择:>";cin>>select;switch(select)        {        case 1:cout<<"请输入要插入的值(-1结束):>";while(cin>>Item, Item!=-1){mylist.push_back(Item);}break;case 2:cout<<"请输入要插入的值(-1结束):>";while(cin>>Item, Item!=-1){mylist.push_front(Item);}break;case 3:mylist.show_list();break;        case 4:            mylist.pop_back();            break;        case 5:            mylist.pop_front();            break;        case 6:            cout<<"请输入要插入的值:>";            cin>>Item;            mylist.insert_val(Item);            break;case 7:cout<<"请输入要删除的值:>";cin>>Item;mylist.delete_val(Item);break;case 8:cout<<"请输入要查找的值:>";cin>>Item;mylist.find(Item);break;        case 9:            mylist.length();            break;        case 10:            mylist.clear();            break;        case 11:            mylist.destroy();            break;        case 12:            mylist.reserv();            break;        case 13:            mylist.sort();            break;default:break;        }    }}