A winter week

The last weekend was packed with contests. First off, the Yandex Cup 2025 onsite final took place in Istanbul early on Saturday (results, top 5 on the left). The usual suspects topped the scoreboard, and Kevin got the highest score in each problem and earned the well-deserved first place. Congratulations!

This was already the 10th cphof-worthy contest of 2025, and with the addition of the upcoming Hacker Cup and the completed without published results TopCoder Marathon Match Tournament (yes, TopCoder is still around! But does anybody know what happened to the results?) it could be 12. That is a big improvement over the recent years, and the overall record of 17 per year in 2016 does not look too far away. Huge thanks to all organizers, and I'm looking forward to the 2026 editions!

Codeforces Round 1069, which reused some of the problems of the Yandex final, took place in parallel (problems, results, top 5 on the left, analysis). A Kevin won here as well, solving problem D with just 6 minutes remaining in the round. Kudos for the perseverance!

The Universal Cup Grand Prix of Poland also took place on Saturday (problems, results, top 5 on the left). The first Kevin, together with his teammates, needed less than half of the contest to wrap things up, almost 90 minutes faster than everybody else. The closest pursuers were the other veteran teams Almost Retired Dandelion and Amstelpark, and I am of course partial to seeing veteran teams perform well. Congratulations!

The M(IT)^2 25-26 Winter Contest followed on Sunday, starting with the Individual Round (problems, results, top 5 on the left, analysis). The second Kevin came out ahead this time, but he had to wait anxiously for quite some time since Gennady had a big penalty time advantage after the first four problems, and therefore could afford to solve the fifth problem twenty minutes later but still win. This did not happen, so congratulations on the victory!

The easiest problem turned out to be (relatively) challenging for me, as I used 12 minutes to get it right while some others needed only 3. It went like this: you are given a string of length <=10⁵. You can replace any occurrence of MIT with TIM and vice versa, and do that as many times as you want. What is the maximum number of occurrences of MITIT you can get? Can you see how to solve and implement this without too much casework?

The Team Round followed a few hours later (problems, results, top 5 on the left, analysis, award ceremony stream). Finally, no Kevins in the first place: team T1 had Jaehyun, Gennady and Sunghyeon instead. Congratulations!

Thanks for reading, and check back next week!