Puzzle from leetcode:
You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
Explanation: 342 + 465 = 807.
The template code provided by leetcode:
My first came out solution just like how we do sum on draft paper:
Time complexity: O(n)
It’s do a little optimization:
Super! Better than 99.99%!