0
点赞
收藏
分享

微信扫一扫

双向链表的基本操作

Alex富贵 2022-04-16 阅读 82

双向链表很多操作只需要在单链表的基础上稍作修改;下面来看看基本操作:

1、定义

typedef struct DNode{
	int data;
	struct DNode* next;
	struct DNode* prior;
}DNode, *DLinkList;

 2、插入

DLinkList DList_Head_Insert(DLinkList& DL)
{
	int x;
	DNode* s;
	DL = (DNode*)malloc(sizeof(DNode));
	DL->next = NULL;
	DL->prior = NULL;
	scanf("%d", &x);
	while (x != 9999)
	{
		s = (DNode*)malloc(sizeof(DNode));
		s->data = x;
		s->next = DL->next;
		if (DL->next)
			DL->next->prior = s;
		s->prior = DL;
		DL->next = s;
		
		scanf("%d", &x);
	}
	return DL;
}

DLinkList DList_Tail_Insert(DLinkList& DL)
{
	DL = (DNode*)malloc(sizeof(DNode));
	DL->next = NULL;
	DL->prior = NULL;
	int x;
	DNode* s, * r;
	r = DL;
	scanf("%d", &x);
	while (x != 9999)
	{
		s = (DNode*)malloc(sizeof(DNode));
		s->data = x;
		r->next = s;
		s->prior = r;
		r = s;
	
		scanf("%d", &x);
	}
	r->next = NULL;
	return DL;
}

两种插入的办法,头插和尾插;

3、打印链表里面的数据

void PrintDList(DLinkList DL)
{
	DL = DL->next;
	while (DL)
	{
		printf("%-3d",DL->data);
		DL = DL->next;
	}printf("\n");
}

4、得到链表中的第i个数据,返回指针

DLinkList GetElem(DLinkList DL,int site)
{
	if (site == 0)
		return DL;
	if (site < 1)
		return NULL;
	DL = DL->next;
	int i = 1;
	while (DL && i++ < site)
		DL = DL->next;
	return DL;
}

5、在第i个位置插入

bool DList_Insert(DLinkList& DL,int site,int e)
{
	if (DL == NULL)
		return false;
	DLinkList p = GetElem(DL, site - 1);
	DNode* r = (DNode*)malloc(sizeof(DNode));
	r->data = e;
	r->next = p->next;
	p->next->prior = r;
	r->prior = p;
	p->next = r;
	return true;
}

6、删除第i个位置的元素

bool DList_Delete(DLinkList& DL, int site)
{
	DLinkList p = GetElem(DL, site - 1);
	if (p == NULL)
		return false;
	DNode* q = p->next;
	if (q == NULL)
		return false;
	p->next = q->next;
	q->next->prior = p;
	free(q);
	return true;
}

操作大概就这么多,可能有的操作的边界问题没有考虑到,就这样吧,依据实际情况而定。

举报

相关推荐

0 条评论