c++实现链表简单操作（单链表、循环链表与双向链表）

链表，对比数组可以节省空间，由数据域与指针域构成一个数据块，操作方便。

1 单链表创建算法思路：

1. 申明一节点p
2. 初始化一空链表
3. 头指针指向NULL，即建立一个带表头节点的单链表
4. 循环查找要插入地方或删除

包括头插与尾插两种方式实现节点插入，c++模板方式构建结构体，简单实现插入与删除节点

#include<iostream>

using namespace std;
template <typename T>
struct Node {
	T data;
	Node<T>* next;
	//Node() { next = NULL; }
};

template <typename T1, typename T2>
struct StaNode {
	T1 data;
	T2 cur;
};
typedef Node<int>* link_type0;
typedef Node<int> value_type0;
typedef  StaNode<int, int>* link_type;
typedef  StaNode<int, int> value_type;

//动态链表
void dyLink(link_type0 head)
{
		link_type0 t;
		head->next = NULL;
		//头插节点
		//for (int i = 0; i < 5; i++)
		//{
		//	t = new value_type;
		//	//t = (link_type)malloc(sizeof(value_type));
		//	t->data = i + 1;
		//	t->next = head->next;
		//	head->next = t;
		//}
		//尾插节点
		link_type0 p = new value_type0;
		p = head;
		for (int i = 0; i < 5; i++)
		{
			t = new value_type0;
			t->data = i + 1;
			t->next = NULL;
			p->next = t;
			p = p->next;
		}
	
		p = head;
		for (int i = 0; i < 5; i++)
		{
			cout << p->data << endl;
			p = p->next;
		}
		//删除节点
		p = head;
		while (p->next && p->next->data != 3)
		{
			p = p->next;
		}
		if (!p->next)
			cout << -1 << endl;
		p->next = p->next->next;
		link_type0 p1 = new value_type0;
		p1 = head->next;
		while(p1)
		{
			cout << p1->data << endl;
			p1 = p1->next;
		}
		//删除整个链表
		p = head;
		link_type0 q;
		while (p)
		{
			q = p->next;
			free(p);
			p = q;
		}
		head->next = NULL;
		p = NULL;
		free(p);
		free(p1);
}
int main()
{
	link_type0 head0 = new value_type0;//动态
    dyLink(head0);

	system("pause");
}

2 循环链表

只是将单链表尾指针由NULL变为头指针地址。在单链表与循环链表判断上，前者判断p->next 不为空，后者判断p->next != head代表循环一圈。

3 双向链表

在单链表基础上，每个节点数据块添加前驱指针即可

template <typename T>
struct Node {
	T data;
	Node<T>* next;
    Node<T>* prior;
};

节点s插入链表中

s->prior = p;
s->next = p->next;
p->next = s;
p->next->prior = s;

删除p所指节点

p->prior->next = p->next;
p->next->prior = p->prior;
free(p);

4 单链表翻转

将节点依次打断，重新连接

link_type0 reverseLink(link_type0 head)
{
	link_type0 p, q, pr;
	q = NULL;
	p = head->next;
	head->next = NULL;
	while (p)
	{
		pr = p->next;
		p->next = q;
		q = p;
		p = pr;
	}
	head->next = q;

	cout << "翻转之后：" << endl;
	link_type0 p1 = new value_type0;
	p1 = head->next;
	while (p1)
	{
		cout << p1->data << endl;
		p1 = p1->next;
	}
	return head;
}