# Leetcode 43 - Multiply strings

Note:

• 123 can be written as 100 + 20 + 3, 456 can be written as 400 + 50 + 6.
• Calculate 100*400, 100*50, ... 3*6, and put them all in an array.
• To calculate 100*400, just calculate num1[0]*num2[0] + trailing 0s.
• Make a helper function addTwoString(n1, n2).

Question:

Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also represented as a string.

Note: You must not use any built-in BigInteger library or convert the inputs to integer directly.

Example:

Code: