README.md

2. Add Two Numbers

Problem

Add the two numbers and return the sum as a linked list.

- linked lists are non-empty and each node contains a single digit
- digits stored in reverse order

Approach

Convert the linked list into integers

• converts linked lists into integers
• compute their sum
• converts the sum back into a linked list

Without converting the linked list into integers

We simplify above appoach by directly building the result linked list instead of converting to an integer and then back to a linked list.

• iterate through both linked list
  • adding corresponding digits along with the crarry from the previous iteration
  • create a new node with the result digit and update the carry for the next iteration