# Sum of two numbers represented by linked lists

Given two numbers represented by two linked lists of size **N1** and **N2**. The task is to return a sum list. The sum list, which is a linked list representation of the addition of two input numbers.

**Input:**

The first line of input contains the number of test cases **T**. For each test case, the first line of input contains the length of the first linked list and the next line contains **N1** elements of the linked list. Again, the next line contains **N2**, and the following line contains M elements of the linked list.

**Output:**

Output the resultant linked list representing the sum of given two linked list.

**Example with explanation:**

Input:
T = 1
N1 = 3
[1->5->4]
N2 = 3
[2->3->5]
Output:
[3->8->9], as 451+532 = 983
Input:
T = 1
N1 = 3
[2->4->3]
N2 = 3
[5->6->4]
Output:
[7->0->8], as 342+465 = 807

We will use the same way of addition as we use to do during elementary school, we will keep track of carry using a variable car and traverse digit by digit sum starting from the head of two linked list which contains least significant digit to most significant digits.

Pseudo Code:Time complexityfor above process isO(max(len(N1,N2))C++ Implementation:Output