C++基础-实现双向链表的创建、插入、删除等简单操作_c++双向链表删除

1、实现双向链表的创建、插入、删除等简单操作

#include <iostream>
#include <stdio.h>
using namespace std;
#define EXIT_FAILURE 0
//结点类
class Node
{
	public:
		int data;
		Node *pPre, *pNext;
};
//双向链表类
class DoubleLinkList
{
	public:
		DoubleLinkList() {
			head = new Node;
			head->data = 0;
			head->pNext = NULL;
			head->pPre = NULL;
		}
		~DoubleLinkList() {
			delete head;
		}
		void CreateLinkList(int n);				//创建链表
		void InsertNode(int position, int d);	//在指定位置处插入结点
		void TraverseLinkList();				//遍历链表
		bool IsEmpty();							//判断链表是否为空
		int GetLength();						//获得链表长度
		void DeleteNode(int position);			//删除指定位置处结点
		void DeleteLinkList();					//删除链表
	private:
		Node *head;
};
void DoubleLinkList::CreateLinkList(int n)
{
	if (n < 0) {
		cout << "输入结点个数错误！" << endl;
		exit(EXIT_FAILURE);
	} else {
		int i = 0;
		Node *pnew, *ptemp;
		ptemp = head;
		i = n;
		while (n-- > 0) {
			cout << "请输入第" << i - n << "个结点值：";
			pnew = new Node;
			cin >> pnew->data;
			pnew->pNext = NULL;
			pnew->pPre = ptemp;
			ptemp->pNext = pnew;
			ptemp = pnew;
		}
	}
}
void DoubleLinkList::InsertNode(int position, int d)
{
	if (position < 0 || position > GetLength() + 1) {
		cout << "输入位置错误！" << endl;
		exit(EXIT_FAILURE);
	} else {
		Node *pnew, *ptemp;
		pnew = new Node;
		pnew->data = d;
		ptemp = head;
		while (position-- > 1)
			ptemp = ptemp->pNext;
		if (ptemp->pNext != NULL)
			ptemp->pNext->pPre = pnew;
		pnew->pNext = ptemp->pNext;
		pnew->pPre = ptemp;
		ptemp->pNext = pnew;
		ptemp = pnew;
	}
}
//遍历链表
void DoubleLinkList::TraverseLinkList()
{
	Node *ptemp = head->pNext;
	while (ptemp != NULL) {
		cout << ptemp->data << " ";
		ptemp = ptemp->pNext;
	}
	cout << endl;
}
//检测链表是否为空
bool DoubleLinkList::IsEmpty()
{
	if (head->pNext == NULL)
		return true;
	else
		return false;
}
//得到当前链表的长度
int DoubleLinkList::GetLength()
{
	int n = 0;
	Node *ptemp = head->pNext;
	while (ptemp != NULL) {
		n++;
		ptemp = ptemp->pNext;
	}
	return n;
}
//删除链表的结点
void DoubleLinkList::DeleteNode(int position)
{
	if (position < 0 || position > GetLength()) {
		cout << "输入数据错误!" << endl;
		exit(EXIT_FAILURE);
	} else {
		Node *pdelete, *ptemp;
		ptemp = head;
		while (position-- > 1)
			ptemp = ptemp->pNext;
		pdelete = ptemp->pNext;
		if (pdelete->pNext != NULL)
			pdelete->pNext->pPre = ptemp;
		ptemp->pNext = pdelete->pNext;
		delete pdelete;
		pdelete = NULL;
	}
}
//删除链表
void DoubleLinkList::DeleteLinkList()
{
	Node *pdelete, *ptemp;
	pdelete = head->pNext;
	while (pdelete != NULL) {
		ptemp = pdelete->pNext;
		head->pNext = ptemp;
		if (ptemp != NULL)
			ptemp->pPre = head;
		delete pdelete;
		pdelete = ptemp;
	}
}
//测试函数
int main()
{
	DoubleLinkList dl;
	int position = 0, value = 0, n = 0;
	bool flag = false;
	cout << "请输入需要创建双向链表的结点个数：";
	cin >> n;
	dl.CreateLinkList(n);
	cout << "打印链表值如下：";
	dl.TraverseLinkList();
	cout << "请输入插入结点的位置和值：";
	cin >> position >> value;
	dl.InsertNode(position, value);
	cout << "打印链表值如下：";
	dl.TraverseLinkList();
	cout << "请输入要删除结点的位置：";
	cin >> position;
	dl.DeleteNode(position);
	cout << "打印链表值如下：";
	dl.TraverseLinkList();
	dl.DeleteLinkList();
	flag = dl.IsEmpty();
	if (flag)
		cout << "删除链表成功！" << endl;
	else
		cout << "删除链表失败！" << endl;
	return 0;
}