LeetCode: Palindrome Linked List Solution

Yeah I skipped the follow-up

Approach

Convert to array and check

Implementation

1/**
2 * Definition for singly-linked list.
3 * function ListNode(val, next) {
4 *     this.val = (val===undefined ? 0 : val)
5 *     this.next = (next===undefined ? null : next)
6 * }
7 */
8/**
9 * @param {ListNode} head
10 * @return {boolean}
11 */
12var isPalindrome = function (head) {
13  let arr = []
14  while (head) {
15    arr.push(head.val)
16    head = head.next
17  }
18  const N = arr.length
19  for (let i = 0; i < Math.floor(N / 2); i++) {
20    if (arr[i] !== arr[N - i - 1]) {
21      return false
22    }
23  }
24
25  return true
26}