Palindrome Linked List Problem Statement

Determine if a given singly linked list of integers is a palindrome. Return true if it is a palindrome, otherwise return false.

Example:

Input:

1 -> 2 -> 3 -> 2 -> 1 -> NULL

Output:

true

Explanation:

The linked list reads the same forwards and backwards, hence it is a palindrome.

Follow Up:

Can you solve the problem in O(N) time complexity and O(1) space complexity iteratively?

Input:

The first line contains an integer 'T' representing the number of test cases. Each test case consists of a single line with elements of the linked list separated by spaces, ending with -1. The -1 is not part of the list.

Output:

For each test case, output “true” or “false” on a new line.

Constraints:

• 1 <= T <= 10
• 0 <= L <= 10⁵
• 1 <= data <= 10⁹ and data != -1

Where L is the number of nodes in the linked list.

Time Limit: 1 sec