C: The reference solution is not correct. An example from random_tests:

Expected 38, but got 39. 
Input: "FNBZVPFQOPKKHEXRQJ IHFJSCONRSL XOAVYFANIEMSBQOHWMGDULMADPCUGCUCQJNOOCQWGSDXXGDSTKVMKWMNKOHQFAIWJVZNX"

Both Python and JavaScript reference solutions return 39 for this input.

Ignore spaces altogether

If the string contains a number, return -1.

These side quests add nothing to the primary task, and should be removed. Uninteresting input preprocessing and validation have been done.

Testing with valid inputs only means no existing solutions will be invalidated.

You have missed this part in the description --> Spaces should not be taken into account.(ignore spaces altogether)

Very unclear on how spaces should be dealt with. Gave up only because of that.

kata hint != kata suggestion

Fixed.

I checked, I didn't find any errors. This typo was as soon as this kata was released. And then it was corrected. If I misunderstood something, please write about it.

The sample tests expect a function named max_len_wiht_condition but the final tests expect max_len_with_condition (Python)

Slow as heck I am

👆 The explanation is correct

No two letters N,O,P can be adjacent to each other in a substring, so:

NOPN OPNO => NOPNOPNO => N, O, P, N, O, P, N, O => 1

So given 'NOPN OPNO', ignoring space is 'NOPNOPNO'. this somehow results to 1?

• (N)OPNOPN(O) should be 2?
• (N)OP(N) (O)PN(O) would be 4
  or?