Hello everyone!

The second round of MemSQL Start[c]UP 3.0 will take place this Saturday, September 30, at 10:05am US/Pacific.

There will be an onsite round at MemSQL HQ and parallel online rounds that will be open for div1 and div2 participants. The online finalists (placed in top 500 in Round 1) will be given 100 MemSQL Start[c]UP T-shirts.

The onsite contestants will be participating from MemSQL HQ using their personal laptops. Breakfast will be served starting at 8:30 am, contest starts at 10:05 am and lunch will be served after the contest. The three winners of the onsite round will be awarded Amazon gift cards for $1000, $500 and $250. Please come early to set everything up.

Here is the list of people who agreed to participate: aandrew, al13n, ToTLeS, architkarandikar, Belonogov, BIT-silence, chenmark, farmersrice, Lewin, LiChenKoh, _M_, NgocHai, fmqjpt, Jatana, SaveVMK, scott_wu, sdya, SnapDragon, winger, Aviously, xiaowuc1, yum, yzyz.

If you haven't accepted the invitation yet or you think that we missed you, please message MikeMirzayanov or cerealguy.

We will update this post with more contest details later.

Good luck!

UPD: For onsite finalists: you are already registered for the corresponding round. You don't need to register anywhere else. For everybody else: choose the corresponding division round. All rounds will be rated for everybody, and we'll make special standings for the official participants of Round 2 (who placed in top 500 in Round 1).

UPD2: All online finalists will be registered in Div. 1 round automatically.

UPD3: Huge thanks to round testers: ashmelev, Errichto, cyand1317, vintage_Vlad_Makeev!

UPD4: You will be able to see results of offsite finalists using this link.

Congratulations to winners!

Onsite finalists:

1. scott_wu — $1000 Amazon gift card!
2. Belonogov — $500 Amazon gift card!
3. xiaowuc1 — $250 Amazon gift card!
4. LiChenKoh
5. sdya

Other finalists and div. 1:

1. tourist
2. Petr
3. ksun48
4. halyavin
5. Arterm

Div. 2:

1. laizenan
2. PSMao
3. lqs2015
4. Ahmed_Abdellah
5. kr_abhinav

MemSQL Start[c]UP 3.0 Round 1 is over!

Congratulations to jqdai0815, Petr, eatmore and tourist on solving all the problems!

Here are our solutions:

MemSQL is excited to announce Start[c]UP 3.0 – the third iteration of the programming competition hosted by Codeforces with an onsite at MemSQL HQ in San Francisco, California.

Start[c]UP 3.0 consists of two rounds. Round 1 is online and takes place on September 16th at 10:35 AM PST. Round 1 follows regular Codeforces rules and consists of at least 5 problems. For this round, the complexity of the problems will be comparable to a regular Codeforces round. There are no eligibility restrictions to participate in the round. The round will be 2.5 hours long, and will be rated.

Round 2 takes place on September 30th at 10:30 AM PST and uses regular Codeforces rules. The complexity of the problems is higher than a regular Codeforces round, the round will be 3 hours long, and will be rated. Only people who finished in the top 500 in Round 1 can participate. The top 100 in round 2 will receive a Start[c]UP 3.0 T-shirt.

For Silicon Valley residents, MemSQL will be hosting up to 25 people on-site during the second round. The winner of the on-site round will be awarded a special prize.

If you are interested in job opportunities/intern positions in MemSQL (San Francisco and Seattle) please fill in the form http://mirror.codeforces.com/memsql2017/apply or you can do it during the registration on the round.

Round 1 has started!

There are 7 problems scored as 500-750-1000-1500-2000-2750-3000. The problems were prepared by pieguy with help from cerealguy and nika. Big thanks to KAN for helping with the contest and cyand1317, vintage_Vlad_Makeev, Arpa for testing.

Очень много задач впихивал на Java, но на следующий спецэффект почему-то до сих пор не обращал внимания.

1. Пишем код, использующий где-нибудь маленькую библиотечную функцию вроде Math.max
2. Запускаем и получаем TL
3. Копипастим эту функцию из библиотеки в свой файл и вызываем скопипасченную функцию
4. Ускорение в несколько раз

Почему-то работает на 32-битных JVM, не проявляется на 64-битных.

Следующий код в запуске Codeforces выдал 876 125 под Java 6 и 687 125 под Java 7.

WTF?

Простая задача для клуба знатоков codeforces.

Mr Bug искал на контесте число остовных деревьев и сделал забавный баг. Ко всеобщему удивлению, решение все же получило Accepted и даже прошло стресс-тестирование. Нам предоставляется код, вычисляющий определитель матрицы по простому модулю.

Внимание, три вопроса:

• (250) Найти в коде баг.
• (500) Функция вызывается от матрицы Кирхгофа графа, из которой удалены последняя строка и столбец. Доказать, что код работает почти правильно (за исключением бага вроде того, на котором падали в сегодняшнем SRM).
• (1000) Сгенерировать граф, в котором не очень много ребер, и для которого получится неправильный ответ.