of course. only change constants.

but the testcases are against that

do you know the concept of null-safe methods? null is not same as empty

I think that string formatting inside loop is slower than stb.WriteString. Am I wrong?

Even better using new StringBuilder(initialLength) constructor since final string length is predictable to avoid memory copy when internal buffer is exhausted

but not for hugh strings efficiently

I thik its innefficient on very hugh strings. Better check one rune by rune to get Unicode-16 full

Fails on strings with subrrogates. It's better transform before to rune slice to get a full support

It only works well on strings where characters are formed by one codepoint. fails for surrogates.

So better use iterators instead access in a binary way

str.split(...) makes strings be corrupted (eg. emojis are splited into 2 codepoints).

Better use Array.from(str) to convert it to array safety

Inefficient for huge strings. better use iterators to check codepoints one by one

Thanks

Ahhhh, ok!

It was for support all optional things mentioned in kata's description such as hastag or 3/6 length color too validating . And using bitwise operators to refresh knowledge

lol

What is the amazing thing?

It's a bad idea mutate input array with shift()