160. implement atob()

Is this helpful ?

few challengers  - accepted / - tried

atob() decodes a string of data which has been encoded using Base64 encoding.

Please implement your own myAtob()

myAtob('QkZFLmRldg==') // 'BFE.dev'
myAtob('Q') // Error

Please don't use atob() directly in your code.

Let's try to solve this problem within 10 mintues.