带头节点的双循环链表

如题；这是一套完整的可运行的代码；需要读者有一定的基础去阅读；

语言是用C语言实现；在C++环境中编写；在C++中可直接运行；在C语言中需要改部分头文件和输出语句；

头文件；这要是代码的声明部分；

 # ifndef _LINKLIST_ # define _LINKLIST_  # include <iostream> using namespace std;  typedef int DataType;  typedef struct Node { 	DataType data; 	struct Node * next; 	struct Node * prior; }LNode, *LinkList;  LinkList CreateLinkList(void); void DestroyLinkList(LinkList * pH); int LengthLinkList(LinkList H); void TraversalLinkList(LinkList H);  LinkList SearchLinkListPos(LinkList H, int pos); LinkList SearchLinkListValue(LinkList H, DataType x); int InsertLinkListPos(LinkList H, int pos, DataType x); int DeleteLinkListPos(LinkList H, int pos, int * val);  # endif 

实现文件；主要是代码的实现；

 # include "Head.h"  LinkList CreateLinkList(void) { 	LinkList H = (LinkList)malloc(sizeof(LNode));  	if (NULL != H) 	{ 		H->data = 0; 		H->prior = H; 		H->next = H;  		return H; 	} 	else 	{ 		cout << "Memory allocate is error! " << endl; 		system("pause"); 		exit(0); 	} }  void DestroyLinkList(LinkList * pH) { 	LinkList H = *pH;  	if (H == H->next) 	{ 		free(H); 		H = NULL;  		*pH = NULL; 		return; 	}  	LinkList p = H->next; 	LinkList q = NULL;  	while (p != H) 	{ 		q = p; 		p = p->next; 		free(q); 		q = NULL; 	}  	free(H); 	H = NULL;  	*pH = NULL; 	return; }  int LengthLinkList(LinkList H) { 	if (H == H->next) 	{ 		return 0; 	}  	LinkList p = H->next; 	int cnt = 0;  	while (p != H) 	{ 		p = p->next; 		cnt++; 	}  	return cnt; }  void TraversalLinkList(LinkList H) { 	if (H == H->next) 	{ 		return; 	}  	LinkList p = H->next;  	while (p != H) 	{ 		cout << p->data << " "; 		p = p->next; 	} 	cout << endl;  	return; }  LinkList SearchLinkListPos(LinkList H, int pos) { 	if (0 == pos) 	{ 		return H; 	}  	LinkList p = H->next;  	int i = 0; 	while ((p != H) && (i < pos - 1)) 	{ 		p = p->next; 		i++; 	}  	if ((p == H) || (i > pos - 1)) 	{ 		cout << "LinkList is not exit or parameter error! " << endl; 		return NULL; 	}  	return p; }  LinkList SearchLinkListValue(LinkList H, DataType x) { 	if (H == H->next) 	{ 		return NULL; 	}  	LinkList p = H->next;  	while ((p != H) && (p->data != x)) 	{ 		p = p->next; 	}  	if (p == H) 	{ 		return NULL; 	} 	else 	{ 		return p; 	} }  int InsertLinkListPos(LinkList H, int pos, DataType x) { 	LinkList p = SearchLinkListPos(H, pos - 1); 	if (NULL == p) 	{ 		return -1; 	}  	LinkList q = (LinkList)malloc(sizeof(LNode)); 	q->data = x;  	q->next = p->next; 	p->next->prior = q; 	p->next = q; 	q->prior = p;  	return 0; }  int DeleteLinkListPos(LinkList H, int pos, int * val) { 	if ((H == NULL) || (H == H->next)) 	{ 		return -1; 	}  	LinkList p = SearchLinkListPos(H, pos - 1); 	if ((NULL == p) || (p->next == H)) 	{ 		return -2; 	}  	*val = p->next->data;  	LinkList q = p->next; 	p->next = q->next; 	q->prior = p; 	free(q); 	q = NULL;  	return 0; } 

Main函数；

 # include "Head.h"  int main(int argc, char ** argv) { 	int val = 0; 	LinkList H = CreateLinkList(); 	for (int i = 0; i < 10; i++) 	{ 		InsertLinkListPos(H, i + 1, i + 1); 	}  	TraversalLinkList(H); 	LinkList p = H->prior; 	cout << p->data << endl;  	while (p != H) 	{ 		cout << p->data << " "; 		p = p->prior; 	} 	cout << endl;  	//LinkList p = H; 	//while (p->next != H) 	//{ 	//	p = p->next; 	//}  	//cout << p->data << endl; 	//p = p->next->next; 	//cout << p->data << endl;  	system("pause"); 	return 0; }

文章来源: https://blog.csdn.net/qinjiawei_156558/article/details/97287102