leetcode-237-Delete Node in a Linked List

Delete Node in a Linked List

Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.

Supposed the linked list is

1 -> 2 -> 3 -> 4

and you are given the third node
with value

3

, the linked list should become

1
-> 2 -> 4

after calling your function.
删除链表的一个节点，但只给你需要删除的那个节点。

依次将后一个节点的val值赋给前一个，最后一个节点无用，将倒数第二个节点的next指向NULL，时间复杂度O（n）

/**
* Definition for singly-linked list.
* struct ListNode {
*     int val;
*     ListNode *next;
*     ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
void deleteNode(ListNode* node) {
while (node->next->next) {
node->val = node->next->val;
node = node->next;
}
node->val = node->next->val;
node->next = NULL;
}
};

要删除的节点是node

直接将node->next的val值赋给node，然后删除node->next

/**
* Definition for singly-linked list.
* struct ListNode {
*     int val;
*     ListNode *next;
*     ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
void deleteNode(ListNode* node) {
node->val = node->next->val;
node->next = node->next->next;
}
};