Hello, Codeforces!

I want to test the system before Good Bye 2016, to be sure that everything works as expected.

I invite you to take part in Testing Round 13. It will start soon, on December, 29, 09:05:00 (UTC). It will be unofficial unrated round. The duration is 75 minutes.

Pretests are unusually weak to trigger more hack.

You may expect interactive problems. Hope for hacks for them.

Thank you,
MikeMirzayanov