Palindrome Linked List

Problem

Return true if the linked-list node values read the same forwards and backwards.

Examples

Example 1

Input: [1,2,2,1]

Output: true

Example 2

Input: [1,2,3]

Output: false

Input and output use JSON-compatible values. For linked-list and tree questions, arrays represent the node structure as described above. Your code should implement solve(input).

Write your solutionImplement solve(input). Your draft is saved in this browser.

Compiler

How to solve Palindrome Linked List

Return true if the linked-list node values read the same forwards and backwards. Compare the first half with the reversed second half. The reference implementation illustrates this approach; check the example and edge cases.

Time and space complexity

O(n) time and O(1) extra space with in-place second-half reversal.

Practise and improve

Choose JavaScript, TypeScript or Python, complete the starter code, then select Run Tests. Request a hint when you need guidance, or choose View solution and confirm if you would like to study the reference implementation.