237 Delete Node in a Linked List

237. Delete Node in a Linked List

1. Question

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 is1 -> 2 -> 3 -> 4and you are given the third node with value3, the linked list should become1 -> 2 -> 4after calling your function.

2. Implementation

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
public class Solution {
    public void deleteNode(ListNode node) {
        if (node == null || node.next == null) {
            return;
        }

        node.val = node.next.val;
        node.next = node.next.next;
    }
}

3. Time & Space Complexity

时间复杂度O(1), 空间复杂度O(1)