another week, another code challenge
given an array of integers, print a sum triangle from it such that the first level has all array elements. from then, at each level number of elements is one less than the previous level and elements at the level is be the sum of consecutive two elements in the previous level.
time to solve another coding challenge.
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 contains a single digit. Add the two numbers and return the sum as a linked list.
You may assume the two numbers do not contain any leading zero, except the number 0 itself.
