使用反向循環的Javascript Base64解碼？

Question

根據此：http://jsperf.com/fors-vs-while/15在javascript中反向運行循環會產生更快的結果。有沒有人聽說過或嘗試使用JavaScript反向解碼Base64字符串？

Answer 1

算法會是這樣的：

1. Pad the input string to a multiple of 3 characters 
    2. Initialize an empty results array 
    3. Looping backwards in the input string taking 3 chars at a time 
    4. convert 3 chars to the 4 Base64 equivalent 
    5. unshift the Base64 string to the results array 
    6. Return the join of the results array.