Two Lists Sum Advanced </i>
Question
Given two numbers represented by two linked lists, write a function that returns sum list.
The sum list is linked list representation of addition of two input numbers.
Example
Input:
First List: 5->6->3 // represents number 563
Second List: 8->4->2 // represents number 842
Output
Resultant list: 1->4->0->5 // represents number 1405
Challenge
Not allowed to modify the lists.
Not allowed to use explicit extra space.
题解1 - 反转链表
在题 Two Lists Sum | Data Structure and Algorithm 的基础上改了下数位的表示方式,前者低位在前,高位在后,这个题的高位在前,低位在后。很自然地可以联想到先将链表反转,而后再使用 Two Lists Sum 的解法。