Advent of Code 2019

[Sergei Nosov]

On Monday, 25 November 2019 at 15:30:47 UTC, Steven Schveighoffer 
wrote:
>
> https://dlang.org/phobos/std_ascii.html#toLower
> https://dlang.org/phobos/std_ascii.html#toUpper
> https://dlang.org/phobos/std_utf.html#byCodeUnit
>
> -Steve

Thanks!

byCodeUnit seems to be the working out alright.

I believe, I've tried `byChar` previously and couldn't make it 
work (because I was under misconception that it has the semantics 
of `byCodeUnit`).