This week in competitive programming

This week contained two TopCoder rounds. The first one was TopCoder SRM 655 on Thursday (problems, results, top 5 on the left). Gennady 'tourist' showed really outstanding performance getting the highest score on all 3 problems, and the highest gain on challenges (+350) to boot - awesome job!

Here's one of the problems Gennady was the fastest to solve - in fact, he spent just 2 minutes and 44 seconds on reading the problem statement and implementing the correct solution. You're given a 20x20 square board initially painted white, and can repeatedly pick a kxk square on it and paint it either black or white, possible over previous painting. Is it possible to obtain the given picture this way?

TopCoder Open 2015 Round 1A followed on Saturday (problems, results, top 5 on the left). Top 250 active contestants were given a bye for this round, but still the competition was tough and Sevenkplus came out on top - congratulations!

The 24-hour Deadline24 contest has also happened this week in Czeladź (results, top 5 on the left). The amazing team of Psyho, marek.cygan and Mojito1 has won - congratulations! Check out Psyho's writeup on one of the problems - it's a very interesting read.

And finally, here's some auto-awesomed spring Zürichsee. See you next week!