LeetCode: 2. Add Two Numbers

Problem: 2. Add Two Numbers

Link: https://leetcode.com/problems/add-two-numbers/

Difficulty: Medium

Description:

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.

Example:

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8
Explanation: 342 + 465 = 807.

Solution: 

Language: Swift

Runtime: 60ms
Memory: 4.0MB