循环链表是还有一种形式的链式存贮结构。它的特点是表中最后一个结点的指针域指向头结点，整个链表形成一个环。

循环链表的操作

1,循环链表的新操作

2, 获取当前游标指向的数据元素

3, 将游标重置指向链表中的第一个数据元素

4,将游标移动指向到链表中的下一个数据元素

5,直接指定删除链表中的某个数据元素

CircleListNode* CircleList_DeleteNode(CircleList* list, CircleListNode* node);

CircleListNode* CircleList_Reset(CircleList* list);

CircleListNode* CircleList_Current(CircleList* list);

CircleListNode* CircleList_Next(CircleList* list);

头文件：

#ifndef _CIRCLE_H_#define _CIRCLE_H_//採用数据封装的方式。防止在主函数改动当中的属性值(有点点像面向对象中的私有属性)typedef void CircleList;typedef struct CircleListNode   //声明指针域{	CircleListNode * next;}CircleListNode;CircleList * CircleList_Create();void CircleList_DesTroy(CircleList * list);void CircleList_Clear(CircleList* list);int CircleList_Length(CircleList* list);int CircleList_Insert(CircleList* list, CircleListNode* node, int pos);CircleListNode* CircleList_Get(CircleList* list, int pos);CircleListNode* CircleList_Delete(CircleList* list, int pos);CircleListNode* CircleList_DeleteNode(CircleList* list, CircleListNode* node);CircleListNode* CircleList_Reset(CircleList* list);CircleListNode* CircleList_Current(CircleList* list);CircleListNode* CircleList_Next(CircleList* list) ;#endif

源文件：

// 循环链表.cpp : 定义控制台应用程序的入口点。//#include "stdafx.h"#include 
      
       #include 
       
        #include "CircleList.h"typedef struct   //定义头结点{	      CircleListNode header;   CircleListNode* sLider;  //游标   int len;}TCircleList;struct Value        //定义数据结构体类型{	    CircleListNode header;  //指针域    int v;                //数据域};int _tmain(int argc, _TCHAR* argv[]){		     int i = 0;    CircleList* list = CircleList_Create();        struct Value v1;    struct Value v2;    struct Value v3;    struct Value v4;    struct Value v5;    struct Value v6;    struct Value v7;    struct Value v8;           v1.v = 1;    v2.v = 2;    v3.v = 3;    v4.v = 4;    v5.v = 5;    v6.v = 6;    v7.v = 7;    v8.v = 8;	        CircleList_Insert(list, (CircleListNode*)&v1, CircleList_Length(list));    CircleList_Insert(list, (CircleListNode*)&v2, CircleList_Length(list));    CircleList_Insert(list, (CircleListNode*)&v3, CircleList_Length(list));    CircleList_Insert(list, (CircleListNode*)&v4, CircleList_Length(list));	//插入到 5 的位置，前面的顺序为 1->2->3->4  	//                      下标： 0  1  2  3	//                             4  5 ...	//故而插入到 5 的位置时  打印的结果应为 ：  1,5,2,3,4。后面的结果也验证了其正确性    CircleList_Insert(list, (CircleListNode*)&v5, 5);	        for(i=0; i
        
         v);    }        while( CircleList_Length(list) > 0 )    {        struct Value* pv = (struct Value*)CircleList_Delete(list, 0);                printf("删除了：%d\n", pv->v);    }    	    CircleList_DesTroy(list);	system("pause");	return 0;}//创建CircleList * CircleList_Create(){	TCircleList* list = (TCircleList*)malloc(sizeof(TCircleList));		if(NULL != list)	{				list->sLider = NULL;		list->header.next = NULL;		list->len = 0;			}	return list;}//销毁void CircleList_DesTroy(CircleList * list){	free(list);}//清空void CircleList_Clear(CircleList* list){	TCircleList * sList = (TCircleList*)list;	if(NULL != sList)	{		sList->len = 0;		sList->header.next = NULL;		sList->sLider = NULL;	}}//获得长度int CircleList_Length(CircleList* list){	TCircleList * sList = (TCircleList*)list;	int len = -1;	if(NULL != sList)	{		len = sList->len;	}	return len;}//插入  int CircleList_Insert(CircleList* list, CircleListNode* node, int pos)  {  TCircleList * sList = (TCircleList*)list;  int i = 0;  int ret = 0;  sList->len;  if((NULL != sList) && (pos>=0) && (NULL != node))  {      CircleListNode * current = (CircleListNode*)sList;      for ( i=0; i
         
          next != NULL; i++)      {      current = current->next;      }            node->next = current->next;             current->next = node;      if(sList->len == 0)      {      sList->sLider = node;            }      ++(sList->len);      if( current == (CircleListNode*)sList )      {      CircleListNode* last = CircleList_Get(sList, sList->len - 1);                  last->next = current->next;      }      ret = 1;              }  return ret;  }  //获得结点CircleListNode* CircleList_Get(CircleList* list, int pos){	TCircleList * sList = (TCircleList*)list;	CircleListNode * resNode = NULL;	int i = 0;	if((NULL != sList) && (pos>=0))	{		CircleListNode * current = (CircleListNode*)sList;		for( i=0; i
          
           next为真正的第一个结点			current = current->next;		}		resNode = current->next;	}	return resNode;}//删除CircleListNode* CircleList_Delete(CircleList* list, int pos){	TCircleList * sList = (TCircleList*)list;	int i = 0;	CircleListNode * resnode = NULL;	CircleListNode* first = sList->header.next;	CircleListNode* last = (CircleListNode*)CircleList_Get(list,sList->len-1);	if((NULL != sList) && (pos >= 0) && (pos < sList->len))	{		CircleListNode * current = (CircleListNode*)sList;		for ( i=0; i
           
            next为真正的第一个结点 current = current->next; } resnode = current->next; current->next = resnode->next; if(first == resnode) { sList->header.next = first->next; last->next = first->next; } if(sList->sLider == resnode) { sList->sLider = resnode->next; } if(sList->len == 0) { sList->header.next = NULL; sList->sLider = NULL; } } sList->len--; return resnode;}//依据结点来删除CircleListNode* CircleList_DeleteNode(CircleList* list, CircleListNode* node){ TCircleList * sList = (TCircleList*)list; CircleListNode* resnode = NULL; int i = 0; if(NULL != sList) { CircleListNode* current = (CircleListNode*)sList; for ( i=0; i
            
             len; i++) { if(node == current->next) { resnode = current->next; break; } current = current->next; } if(NULL != resnode) { CircleList_Delete(sList,i); } } return resnode;}//将游标重置回第一个元素CircleListNode* CircleList_Reset(CircleList* list) { TCircleList* sList = (TCircleList*)list; CircleListNode* ret = NULL; if( sList != NULL ) { sList->sLider= sList->header.next; ret = sList->sLider; } return ret;}//获得当前游标下的结点CircleListNode* CircleList_Current(CircleList* list) { TCircleList* sList = (TCircleList*)list; CircleListNode* ret = NULL; sList->len; sList->header; sList->sLider; if( sList != NULL ) { ret = sList->sLider; } return ret;}//将游标移到下一个结点并获得当前移动前的结点CircleListNode* CircleList_Next(CircleList* list) { TCircleList* sList = (TCircleList*)list; CircleListNode* ret = NULL; if( (sList != NULL) && (sList->sLider != NULL) ) { ret = sList->sLider; sList->sLider = ret->next; } return ret;}
            
           
          
         
        
       
      

执行结果：

15234删除了：1删除了：5删除了：2删除了：3删除了：4请按随意键继续. . .

如有错误，望不吝指出。