Clarification: are there 6 or 7 characters?

[luboslives]

Hi guys, very cool project. I found it via your article.

In that article, you detail how you use the 6 special characters during the encoding/compression phases. But in your readme here and in your source code, you use 7 characters. The one that's left out of the article is U+2061 (Function Application). So just for clarification, is that one truly a web-safe, cross-platform invisible character? And do you use it in that second compression step to replace 2 Cs or 2 Ds?

[Kandavel A]

I would like to thank you in advance for helping us notice the inconsistency in the article to that of the source code which we overlooked. So what happened was, we submitted our article earlier for review on 24th of March, which got featured yesterday, while we found a new invisible character in the meantime and modified our code which was published yesterday. We will be editing our article asap and sorry for the inconvenience caused!

To make things clear all of the 7 invisible characters are web-safe and cross-platform.
Since we had 3 extra characters apart from the 4 used in the first stage of compression,
we used them in 2nd level compression to replace top 3 repeated pairs among(2 As, 2 Bs, 2Cs, 2 Ds)
for further compression.

Assuming I've cleared your issue, I'm closing this.