Description
Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.
给定一个单链表中的一个等待被删除的节点(非表头或表尾)。请在在 O(1) 时间复杂度删除该链表节点。
Note: 1 ≤ m ≤ n ≤ length of list.
Examples
Input: head = [4,5,1,9], node = 5
Output: [4,1,9]
Explanation: You are given the second node with value 5, the linked list should become 4 -> 1 -> 9 after calling your function.
Input: head = [4,5,1,9], node = 1
Output: [4,5,9]
Explanation: You are given the third node with value 1, the linked list should become 4 -> 5 -> 9 after calling your function.
Answer
Create a new node to represent the next node of the input and let the input node to be its next node.
Time Complexity
O(1)
Code
C++
class Solution {
public:
void deleteNode(ListNode* node) {
if(!node || !node->next) return;
ListNode* dummy = node->next;
node->val = dummy->val;
node->next = dummy->next;
}
};
