The expected output is a single string with each row separated with line break.
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Oh.... Ok I got it. Thanks

You wrote the answer in the question. 6=1, 12=2, 18=3 ... Try to figure out the logic of these equations

In the example, input 6 = 1 line full of ■,
input 12 = 2 ■ lines,
input 18 = 3 ■ lines.
Why? Is there any special rules for those ■ lines?

Ok, I thought putting in assertions will result in the same visual output as logs (kudos! ~~

no, the assertion message is ignoring formatting. That's why the logs are there (unless I'm missing something?)

Logs in JS should be removed and placed as assertion messages

Oh. Finally understand the logic of flat rows.
Just did it. Odd n`s are foooo

the odd values are a mistake I did when I translated the kata. It should be corrected now (reset the trainer/refresh the page if it is still persisting)

thanks

All examples my code does perfectly, but test cases if very "bad".
When n is odd - heart is very asimetric, and strange.
Rows of ■■■■■■ in test cases is placed not by the same logic, as in examples

(forgot to close)

oops sorry about that. Should be good, now...

Hint: n>=6 and look at examples values