Add Strings is an example of string problems. In this post we will see how we can solve it in Javascript.

Problem Description

Given two non-negative integers num1 and num2 represented as string, return the sum of num1 and num2.


  1. The length of both num1 and num2 is < 5100.
  2. Both num1 and num2 contains only digits 0-9.
  3. Both num1 and num2 does not contain any leading zero.
  4. You must not use any built-in BigInteger library or convert the inputs to integer directly.

Solution: Please check the main.js snippet for the solution. If you have different approach in mind or have any suggestion for this implementation feel free to share in the comment below. Thanks!

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