I am trying to solve a problem of LinkedList on leetcode in javascript language but out of 86 test cases 74 cases are passed but at 75 I am getting an error Output Limit Exceeded.

Problem:

Given the head of a singly linked list, return true if it is a palindrome.

Examples:

Input: head = [1,2,2,1]
Output: true

Input: head = [1,2]
Output: false

My code:

let array = [];
let list = head;
while (list) {
  array.push(list.val)
  console.log("array1", array)
  list = list.next;
}

let list2 = head;
while (list2) {
  let out = array.pop()
  if (out === list2.val) {
    list2 = list2.next;
  } else {
    return false
  }
}

return true

Last executed input: [3,8,9,3,2,8,9,1,8,9,9,8,5,2,5,4,4,4,3,9,7,5,0,5,8,6,3,3,8,0,7,3,7,7,1,1,1,7,0,2,8,1,8,7,2,9,5,2,9,7,4,8,...]

I am not able to understand why I am getting a Limit exceeded error? Is it due to too many inputs? Or Issue is in my code? If the issue is with inputs then How can I solve this problem in Javascript?

I am trying to solve a problem of LinkedList on leetcode in javascript language but out of 86 test cases 74 cases are passed but at 75 I am getting an error Output Limit Exceeded.

Problem:

Given the head of a singly linked list, return true if it is a palindrome.

Examples:

Input: head = [1,2,2,1]
Output: true

Input: head = [1,2]
Output: false

My code:

let array = [];
let list = head;
while (list) {
  array.push(list.val)
  console.log("array1", array)
  list = list.next;
}

let list2 = head;
while (list2) {
  let out = array.pop()
  if (out === list2.val) {
    list2 = list2.next;
  } else {
    return false
  }
}

return true

Last executed input: [3,8,9,3,2,8,9,1,8,9,9,8,5,2,5,4,4,4,3,9,7,5,0,5,8,6,3,3,8,0,7,3,7,7,1,1,1,7,0,2,8,1,8,7,2,9,5,2,9,7,4,8,...]

I am not able to understand why I am getting a Limit exceeded error? Is it due to too many inputs? Or Issue is in my code? If the issue is with inputs then How can I solve this problem in Javascript?

• javascript
• arrays
• linked-list
• palindrome

• push and pop on an array is probably causing the time issue. You may want to try a different approach. – rcgldr Commented Apr 18, 2022 at 20:25
• 1 Having a console.log in your loop is going to slow down the process too. – trincot Commented Apr 19, 2022 at 14:02

2 Answers 2

console.log is trapped by the LeetCode framework, which sets a limit on the total size of the output you can generate. As your first loop calls it in every iteration, printing the array of already collected values each time, you are producing output in the order of 3