ChunYu's Algorithm Library

237. Delete a Node in a Linked List

Last Updated: 2020.06.02

Table of Contents

Resources
Solution: O(1) / O(1)

Resources

Question Source: Leetcode

Solution: O(1) / O(1)

Intuition

Since we don’t have the pointer to the previous node, we can only get rid of the next node.

IMG 7D6526D2B533 1

Have given node take on the value of the next node
Set the pointer for given node to the next next node

This effectively results in the singly-linked list looking like it has “deleted” the given node.

Code

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution:
    def deleteNode(self, node):
        """
        :type node: ListNode
        :rtype: void Do not return anything, modify node in-place instead.
        """
        node.val = node.next.val
        node.next = node.next.next