should be fixed

fixed

Oops! Thanks for noticing, I checked if the spin is random and forgot to check the rest two.

The function has side effect so I added () to it and it seems to be working now.

Should be fixed after migration to Node 18.

You are right, I should always use the variable slow to move one step, rather than using fast for a different purpose.

Fixed some time ago in this fork

i resolved the ambiguity by adding the following comment in the C initial code:

// it is guaranteed that s1 and s2 have room for
// 1 + max(strlen(s1), strlen(s2)) bytes

duplicate of this issue

Thank you for the response, sorry about that that's my first translation :)
I Removed comments and replace the placements.

I think Unnamed's explanation makes sense, though it is doubtful that one would ever need an array of all the integers from 1 to SIZE_MAX. But in any case it's too late to change the prototype now after so many completions. The function's contract has two much more serious flaws: allocating a heap array whereas the length is known in advance and an output parameter would be more idiomatic; and the completely redundant reporting of the length from inside the function. This is essentially an old, legacy C kata.

raised there as an issue

My main concern is with overloading the console output. It goes against the submission test guidelines.

Tests should not print excessively to standard output. Console output is limited to 1.5 MB and when the limit is reached, the test suite is aborted by the runner and marked as failed. Users sometimes debug their solutions by printing to stdout, and when the test suite itself uses up a significant fraction of the buffer, users may not have enough left for debugging. This especially applies to kata which output HTML to create some visualizations: such HTML uses up a lot of the buffer space allowed for stdout. Ideally, the test suite should give detailed output only when a test fails.

A fair compromise would be to revert the behavior of the submission tests while still printing the visualizations for the sample tests.

Done.

Done in this fork

Fixed.