What's KBB?

That's the question I got asked a lot lately. In short, KBB was a series of competitions that I wrote for the Olimpiade forum. The participants were all Indonesian Olympiad trainees, and they are surprisingly good. Sometimes they found solutions that are completely different from mine but just as original if not more, and I will post their solutions here as well.

• There have been 3 KBBs total, and I'm planning to write all the problems and solutions here for archival purposes. I started with KBB2 because I somehow lost the problems to KBB1. When I do find them, I will surely post them here.


• Each KBB consists of 10 problems, 2 from each field. They are ordered in ascending difficulty (1 = easiest, 10 = hardest). Of course, difficulty itself is a very elusive and relative term, so I must say that they are ordered in estimated difficulty. As such, problem 1 to 5 consist of 1 problem of each field, and so do problem 6 to 10. You can think problem 1 to 5 as the "warm up" problems and problem 6 to 10 as the real interesting ones.


• I can say that I wrote all of these problems. Again, writer of a problem is sometimes a very controversial subject. Let's just say I get the inspirations for these problems somewhere else but the final version themselves (including the numbers) are all mine.