C-链表增删结点的问题(16)

Tip:下面代码是通过结构体中某个值去实现的判断是实现增删的,具体依靠个人业务不同

void insert_element(struct Node *header,int keywordVal,int val){
	
	struct Node *temp=header;
	struct Node *mPrevious=NULL;
	while (temp!=NULL)
	{
		if (temp->val==keywordVal)
		{
			//先连后断
			struct Node *pNewNode=(struct Node *)malloc(sizeof(struct Node));
			pNewNode->val=val;
			pNewNode->pNext=temp->pNext;
			if (mPrevious!=NULL)
			{
				mPrevious->pNext=pNewNode;
				pNewNode->pPrevious=mPrevious;
			}
		}
		temp=temp->pNext;
		mPrevious=temp;
	}
}

struct Node * delete_element(struct Node *header,int keywordVal){
	struct Node *mCurren=header;
	struct Node *mPrivious=NULL;
	struct Node *mNext=NULL;
	//删除第一个节点：只需要将head指向第二个节点
	if (header->val==keywordVal)
	{
		return pHeader->pNext;
	}
	
	while (mCurren!=NULL)
	{
		//删除最后一个节点，只需要将指向最后一个节点的指针（引用）指向NULL(null)
		if (mCurren->pNext==NULL&&mCurren->val==keywordVal)
		{
			mPrivious->pNext=NULL;
		}
		//删除中间节点，只要将需要将指向需要删除节点的指针（引用）指向需要删除节点的下一个节点
		else if(mCurren->val==keywordVal)
		{
			mNext=mCurren->pNext;
			mPrivious->pNext=mNext;
			mNext->pPrevious=mPrivious;
		}
		mPrivious=mCurren;
		mCurren=mCurren->pNext;
	}
	return header;
}

运行如下代码:

结果: