Sorry for my bad English >__<
I will host a small contest called "Weekly Training Farm #15" today.
The exact time is 2nd December 12:00 UTC. It's just about 4 hours before Codeforces Round #383.
Weekly Training Farm Contest Series are hosted in Codeforces group tw-icpc-blog
All problem are prepared by me. This time all problems are my original problems.
You can see the last contest Weekly Training Farm #14 to understand the style of problems.
UPD: The contest starts in around 6 hours! You can register contest now.
UPD 2: 15 minutes remaining!
UPD 3: If you can read Chinese(Traditional), you can find editorial Here.