C++实现循环链表

实现效果如下：

#include
using namespace std;
typedef int T;

//循环链表
class Node
{
public:
	T data;
	Node* next;
};

class CirLink
{
public:
	CirLink();
	~CirLink();
	void InsertLink();  //尾插
	void ValueInsert(); //任意位置插入指定值
	void SortLink();    //排序
	void ShowLink();    //显示
	void ValueDelete();  //删除指定值
	void FindLink();    //查找指定值

private:
	Node* head;
	Node* rear;
	T length;
};

CirLink::CirLink()
{
	head = new Node;
	rear = head;
	rear->next = head;
	length = 0;
}

void CirLink::InsertLink()
{
	Node* ptemp = head;
	cout << "请向循环链表中输入数据：" << " ";
	rear = new Node;
	cin >> rear->data;  cout << endl;
	rear->next = head->next;
	ptemp->next = rear;
	ptemp = ptemp->next;
	length++;
}

void CirLink::ValueInsert()  //任意位置插入指定值
{
	int i, e = 0;
	Node* ptemp = new Node;
	cout << "请输入插入位置：" << " ";
	cin >> i;  cout << endl;
	cout << "请输入插入数据：" << " ";
	cin >> ptemp->data;  cout << endl;

	Node* qtemp = head;
	for (int j = 0; j < i - 1; j++) {
		qtemp = qtemp->next;
	}
	if ((qtemp->next)->next == head) {
		ptemp->next = head;
		(qtemp->next)->next = ptemp;
	}
	else {
		ptemp->next = qtemp->next;
		qtemp->next = ptemp;
	}
	ptemp = qtemp = NULL;
	length++;
}

void CirLink::SortLink()
{
	Node* p, * q;
	p = head->next;
	while (p != head) {
		q = p->next;
		while (q != head) {
			if (p->data > q->data) {
				int e = p->data;
				p->data = q->data;
				q->data = e;
			}
			q = q->next;
		}
		p = p->next;
	}
}

void CirLink::ShowLink()
{
	if (head->next == head) {
		cout << "空表！" << endl;
	}
	Node* ptemp = head->next;
	while (ptemp != head) {
		cout << "循环链表中的元素为：" << ptemp->data << " ";
		ptemp = ptemp->next;
	}
	cout << endl;
}

void CirLink::FindLink()
{
	Node* p = head->next;  int k = 1;
	cout << "输入查找值：" << " ";
	int e = 0;   cin >> e;
	while ((p != head) && (p->data != e)) {
		p = p->next;
		k++;
	}
	if (p == head) {
		cout << "此数值不存在！" << endl;
	}
	else {
		cout << "此数值所在位置为：" << k << endl;
	}
}

void CirLink::ValueDelete()
{
	Node* p = head->next;  Node* q = head;  int k = 1;
	cout << "输入删除值：" << " ";
	int e = 0;   cin >> e;
	while ((p != head) && (p->data != e)) {
		p = p->next;
		q = q->next;
		k++;
	}
	if (p == head) {
		cout << "此数值不存在！" << endl;
	}
	else {
		q->next = p->next;
		delete p; p = NULL;
		cout << "此数值已删除！" << endl;
		length--;
	}
}

CirLink::~CirLink()
{
	Node* ptemp = head->next;
	while (head->next != head) {
		head->next = ptemp->next;
		delete ptemp;
		ptemp = head->next;
	}
	rear = head;  ptemp = NULL;
}

int main()
{
	CirLink s;
	s.InsertLink();
	s.InsertLink();
	s.InsertLink();
	s.InsertLink();
	s.ShowLink();

	s.ValueInsert();
	s.ShowLink();
	s.FindLink();
	s.ValueDelete();
	s.ShowLink();

	

	system("pause");
	return 0;
}