C++链表节点的添加和删除介绍

struct Node {
	int data;
	struct Node* next;
};

struct Node* createList() {
	//创建一个指针来表示表头
	struct Node* headNode = (struct Node*)malloc(sizeof(struct Node));
	headNode->next = NULL;
	return headNode;
}

struct Node* createNode(int data) {
	//创建一个新的指针节点
	struct Node* newNode = (struct Node*)malloc(sizeof(struct Node));
	//结构体变量初始化
	newNode->data = data;
	newNode->next = NULL;
	return newNode;
}

void insertNodeByHead(struct Node* headNode, int data) {
	struct Node* newNode = createNode(data);
	newNode->next = headNode->next;
	headNode->next = newNode;
}

void insertNodeByTail(struct Node* headNode, int data) {
	struct Node* newNode = createNode(data);
	while (headNode->next != NULL)
	{
		headNode = headNode->next;//找到最后一个节点
	}
	headNode->next = newNode;
	newNode->next = NULL;
}

void insertNodeByCenter(struct Node* headNode, int data, int i) {
	struct Node* posNode = headNode;
	/*struct Node* posNodeFront = headNode;*/
	struct Node* newNode = createNode(data);
	if (posNode == NULL) {
		printf("无法查找此数据，链表为空\n");
	}
	else {
		while (posNode->data != i) {
			posNode = posNode->next;//前面位置到达了后面节点的位置
			/*posNode = posNodeFront->next;*///后面位置变成了原来位置的下一个
			if (posNode == NULL) {
				printf("未找到此数据\n");
				break;
			}
		}
		newNode->next = posNode->next;
		posNode->next = newNode;
	}
}