数据结构-链表3-循环链表

LinkList.h

#ifndef LINKLIST_H
#define LINKLIST_H
#define _CRT_SECURE_NO_WARNINGS
#include<stdlib.h>
#include<stdio.h>
#include<string.h>

//链表小结点
typedef struct CIRCLELINKNODE {
	struct LinkNode  *next;
}CircleLinkNode;

//链表结构体
typedef struct CIRCLELINKLIST {
	CircleLinkNode head;
	int size;
}CircleLinkList;

//打印回调
typedef void(*PRINTNODE)(CircleLinkNode*);
//比较回调
typedef int(*COMPARENODE)(CircleLinkNode*, CircleLinkNode*);

#define COMPARENODE_TRUE 1
#define COMPARENODE_FALSE 0

//初始化链表
CircleLinkList* Init_LinkList();

//插入
void InsertByPos_LinkList(CircleLinkList *clist, int pos, CircleLinkNode *data);

//根据位置删除元素
void RemoveByPos_LinkList(CircleLinkList *clist, int pos);


//根据值去删除
void RemoveByValue_LinkList(CircleLinkList *clist, CircleLinkNode* data, COMPARENODE compare);

//查找
int FindByValue_LinkList(CircleLinkList *clist, CircleLinkNode *data, COMPARENODE compare);

//返回第一个元素
CircleLinkNode* Front_LinkList(CircleLinkList *clist);

//返回链表大小
int GetSize_LinkList(CircleLinkList *clist);

//打印结点
void Print_LinkList(CircleLinkList *clist, PRINTNODE print);

//释放链表内存
void FreeSpace_LinkList(CircleLinkList *clist);

//是否为空
int IsEmpty_LinkList(CircleLinkList *clist);

#endif

LinkList.c

#include"LinkList.h"

//初始化链表
CircleLinkList* Init_LinkList()
{
	CircleLinkList * clist = (CircleLinkList*)malloc(sizeof(CircleLinkList));
	clist->head.next = &(clist->head);  //循环链表 指向自己
	clist->size = 0;
	return clist;
}

//插入
void InsertByPos_LinkList(CircleLinkList *clist, int pos, CircleLinkNode *data)
{
	if (clist == NULL)
	{
		return;
	}
	if (pos<0 || pos>clist->size)
	{
		pos=clist->size;
	}
	if (data == NULL)
	{
		return;
	}
	//根据位置查找前一个结点
	//辅助指针变量 
	//辅助结点：插入节点的前一个结点
	CircleLinkNode *pCurrent = &(clist->head);
	for (int i = 0; i < pos; i++)
	{
		pCurrent=pCurrent->next;
	}
	//新数据插入链表
	data->next=pCurrent->next;
	pCurrent->next = data;

	clist->size++;
}

//根据位置删除
void RemoveByPos_LinkList(CircleLinkList *clist, int pos)
{
	if (clist == NULL)
	{
		return;
	}
	if (pos<0 || pos>clist->size)
	{
		return;
	}
	//根据pos找上一个结点
	//辅助结点：插入节点的前一个结点
	CircleLinkNode *pCurrent = &(clist->head);
	for (int i = 0; i < pos; i++)
	{
		//pCurrent->next = pCurrent;
		pCurrent = pCurrent->next;
	}
	//缓存当前结点的下一个结点
	CircleLinkNode *pNext = pCurrent->next;
	pCurrent->next = pNext->next;
	//等价pCurrent->next = pCurrent->next->next;
	clist->size--;
}
//根据值去删除
void RemoveByValue_LinkList(CircleLinkList *clist, CircleLinkNode* data, COMPARENODE compare) {
	if (clist == NULL)
	{
		return;
	}
	if (data == NULL)
	{
		return;
	}

	//循环链表,不能一直循环
	CircleLinkNode* pPre = &(clist->head);
	CircleLinkNode* pCurrent = pPre->next;
	int i = 0;
	for (i = 0; i < clist->size; i++)
	{
		if (compare(pCurrent,data) == COMPARENODE_TRUE)
		{
			pPre->next = pCurrent->next;
			break;
		}
		pPre = pCurrent;
		pCurrent = pPre->next;
	}
	clist->size--;
}

//获得第一个元素
CircleLinkNode* Front_LinkList(CircleLinkList *clist)
{
	if (clist == NULL)
	{
		return NULL;
	}
	return clist->head.next;
}

//是否为空
int IsEmpty_LinkList(CircleLinkList *clist) {
	if (clist == NULL)
	{
		return -1;
	}
	if (clist->size == 0)
		return COMPARENODE_TRUE;
	return COMPARENODE_FALSE;
}


//查找
int FindByValue_LinkList(CircleLinkList *clist, CircleLinkNode *data, COMPARENODE compare)
{
	if (clist == NULL)
	{
		return -1;
	}
	if (data==NULL)
	{
		return -1;
	}
	//辅助结点：插入节点的前一个结点
	CircleLinkNode *pCurrent = clist->head.next;
	int flag = -1;
	for (int i = 0; i < clist->size; i++)
	{
		if (compare(pCurrent, data) == COMPARENODE_TRUE)
		{
			flag = i;
			break;
		}
		pCurrent = pCurrent->next;
	}
	/*while (pCurrent != NULL)
	{
		if (compare(pCurrent, data) == 0)
		{
			flag = index;
			break;
		}
		index++;
		pCurrent = pCurrent->next;
		if (pCurrent->next ==&( pCurrent->head))
		{
			pCurrent->next = pCurrent;
		}
	}*/
	return flag;

}


//返回链表大小
int GetSize_LinkList(CircleLinkList *clist)
{
	if (clist == NULL)
	{
		return -1;
	}
	return clist->size;
}

//打印
void Print_LinkList(CircleLinkList *clist, PRINTNODE print)
{
	if (clist == NULL)
	{
		return;
	}
	CircleLinkNode *pCurrent = clist->head.next;
	for (int i = 0; i < clist->size; i++)
	{
		if (pCurrent == &(clist->head))
		{
			pCurrent = pCurrent->next;
			printf("------------\n");
		}
		  
		print(pCurrent);
		pCurrent = pCurrent->next;
	}
	printf("---------------\n");
	/*
	if (pCurrent == &(clist->head))
		pCurrent = pCurrent->next;*/
	return;
}
//释放链表内存
void FreeSpace_LinkList(CircleLinkList *clist)
{
	if (clist == NULL)
	{
		return;
	}
	free(clist);
}

循环链表.c

#include"LinkList.h"
typedef struct PERSON
{
	CircleLinkNode node;
	char name[64];
	int age;
}Person;

void print(CircleLinkNode *data)
{
	Person *p = (Person*)data;
	printf("Name:%s age:%d\n", p->name, p->age);
}

int compare(CircleLinkNode *node1, CircleLinkNode *node2)
{
	Person *p1 = (Person*)node1;
	Person *p2 = (Person*)node2;
	//if (p1->age == p2->age && p1->name == p2->name)
	if(strcmp(p1->name,p2->name)==0 && p1->age==p2->age)
	{
		return COMPARENODE_TRUE;
	}
	return COMPARENODE_FALSE;
}

int main()
{
	Person p1, p2, p3, p4, p5;
	strcpy(p1.name, "aaa");
	strcpy(p2.name, "bbb");
	strcpy(p3.name, "ccc");
	strcpy(p4.name, "ddd");
	strcpy(p5.name, "eee");

	p1.age = 10;
	p2.age = 20;
	p3.age = 30;
	p4.age = 40;
	p5.age = 50;

	CircleLinkList *clist = Init_LinkList();

	InsertByPos_LinkList(clist, 100, (CircleLinkNode *)&p1);
	InsertByPos_LinkList(clist, 100, (CircleLinkNode *)&p2);
	InsertByPos_LinkList(clist, 100, (CircleLinkNode *)&p3);
	InsertByPos_LinkList(clist, 100, (CircleLinkNode *)&p4);
	InsertByPos_LinkList(clist, 100, (CircleLinkNode *)&p5);

	//打印
	Print_LinkList(clist,print);

	Person pDel;
	strcpy(pDel.name, "ccc");
	pDel.age = 30;

	//根据值删除
	RemoveByValue_LinkList(clist,(CircleLinkNode*)&pDel, compare);

	//打印
	printf("删除ccc后打印---------------------\n");
	Print_LinkList(clist, print);

	int pos=FindByValue_LinkList(clist, (CircleLinkNode *)&p2,compare);
	printf("bbb的位置：%d\n ",pos);

	FreeSpace_LinkList(clist);
	system("pause");
	return 0;
}

//////////////////////////////运行结果//////////////////////////
/*
Name:aaa age:10
Name:bbb age:20
Name:ccc age:30
Name:ddd age:40
Name:eee age:50
---------------
删除ccc后打印---------------------
Name:aaa age:10
Name:bbb age:20
Name:ddd age:40
Name:eee age:50
---------------
bbb的位置：1
请按任意键继续. . .
*/

运行结果：