Leetcode 2130: Maximum Twin Sum of a Linked List

Pierre-Marie Poitevin
3 min readJan 9, 2022

In this problem, we are working with Linked Lists and need to return the maximum sum of “twin” elements, defined in the following way:

In a linked list of size n, where n is even, the ith node (0-indexed) of the linked list is known as the twin of the (n-1-i)th node, if 0 <= i <= (n / 2) - 1.
For example, if n = 4, then node 0 is the twin of node 3, and node 1 is the twin of node 2. These are the only nodes with twins for n = 4.
The twin sum is defined as the sum of a node and its twin.

Given the head of a linked list…

--

--