very clever

nice

great job

From MDN:
NEVER USE eval()!
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/eval#never_use_eval!
:)

This is clever and nice use of recurssion.

This should be voted the best practice. This answer has O(1) time complexity for lookups vs O(n) used in the higher ranked answers. Nice job.

Using eval may cause JS-engine not to use some optimizations on compilation stage.

Nice catch :D

(n==-7) ? true :

it sounds pity but I made "fitting the response" otherwise I wouldn't discuss here anything

my solution is not using hooks because it didn't work as I expected and I've rewritten it with class then

your solution is not using hooks at all since you cannot use hooks inside class components. so your import of useState and useRef is pointless. there is no need to use refs anyway if you implement a function component with hooks.

Ranking cannot be changed

The length of the firstname is added to the sum of these ranks hence a number som.

reduce difficulty to 6kyu