Just why? Challenge 6 (“Advanced” by the way) is straightforward, Challenge 7 “Pro” is a bit tricky but also not hard to get - but challenge 3 is the most complex of them all (at least for me).
What’s the point of putting them into such a strange order?
Course: https://www.educative.io/collection/10370001/5550095527313408
Lesson: https://www.educative.io/collection/page/10370001/5550095527313408/6448854095364096