C++实现双向链表

代码实现效果如下：

#include
using namespace std;

//双向链表
class Node
{
public:
	int data;
	Node* prior;
	Node* next;
};

class DulLink
{
public:
	DulLink();
	~DulLink();
	void CreatLink();     //创建
	void ShowLink();      //显示
	void FindLink();     //查找
	void InsertLink();   //插入元素
	void ValueDeleLink(); //删除指定数值

private:
	Node* head;
	int length;
};

DulLink::DulLink()
{
	head = new Node;
	head->prior = head->next = head;
	length = 0;
}

void DulLink::CreatLink()
{
	Node* p = head->prior;
	Node* pnew = new Node;
	cout << "输入数值：" << " ";
	cin >> pnew->data;  cout << endl;
	head->prior = pnew;
	pnew->next = head;
	p->next = pnew;
	pnew->prior = p;
	p = head->prior;
	length++;
}

void DulLink::ShowLink()
{
	Node* p = head->next;
	while (p != head) {
		cout << "链表元素为：" << p->data << " ";
		p = p->next;
	}
	cout << endl;
}

void DulLink::FindLink()
{
	cout << "输入查询数值：" << " ";
	int e = 0;  cin >> e;  cout << endl;
	int k = 1;  Node* p = head->next;
	while (p != head  && p->data != e) {
		p = p->next;
		k++;
	}
	if (p == head) {
		cout << "不存在！" << endl;
	}
	else {
		cout << "位置为：" << k << endl;
	}
}

void DulLink::InsertLink()
{
	cout << "输入插入位置：" << " ";
	int k = 0; cin >> k; cout << endl;
	Node* ptemp = head;
	if (k > 0 && k <= length+1) {
		for (int i = 0; i < k; i++) {
			ptemp = ptemp->next;
		}
		Node* pnew = new Node;
		cout << "输入数值: " << " ";
		cin >> pnew->data; cout << endl;
		pnew->next = ptemp;
		(ptemp->prior)->next = pnew;
		pnew->prior = ptemp->prior;
		ptemp->prior = pnew;
		length++;
	}
}

void DulLink::ValueDeleLink()
{
	int e = 0; int k = 1; 
	Node* p = head->next;
	cout << "输入删除值：" << " ";
	cin >> e;  cout << endl;
	while (p != head && p->data != e) {
		p = p->next;
		k++;
	}
	if (p == head) {
		cout << "无此值！" << endl;
	}
	else {
		cout << "已删除元素：" << p->data << "  位置为：" << k << endl;
		p->prior->next = p->next;
		p->next->prior = p->prior;
		delete p; p = NULL;
	}
}

DulLink::~DulLink()
{
	Node* p = head->next;
	while (p != head) {
		p = p->next;
		delete p->prior;
	}
	delete head;
	head = p = NULL;
}

int main()
{
	DulLink s;
	s.CreatLink();
	s.CreatLink();
	s.CreatLink();
	s.ShowLink();
	s.InsertLink();
	s.ShowLink();
	s.ValueDeleLink();
	s.ShowLink();
	s.FindLink();

	system("pause");
	return 0;
}