really nice problems RetiredAmrMahmoud :)))

(many people will fail on C) Why do think so? what's the deal? :D

You should have sent the feedback before the round ended. I did send a feedback before the round, and received a response within 20-30 minutes. You may receive a mail soon, because of the load at the current moments(testing, grading, manual submissions...etc).

Yes I got a response, and sent my solution. Now, waiting for adding the problem before the round ends(as they said).

"If you're having trouble downloading the input for Autocomplete or Corporate Gifting in 6 minutes, please submit a feedback request by clicking "Give Feedback" at the bottom of any problem page."

So you have to send a feedback and follow instructions.

I just hope that the round won't be "boring" :))

You Didn't read this Note:

"Note It's OK if all the numbers are in the same set, and the other one is empty."

By the way, I got WA too in this case :(

"May the Odds be in your favor!" :D