alex_ita's blog

By alex_ita, history, 4 years ago, In English

Hello. I recently had an interview and have been given a weird problem. I have a number M (up to 10⁹) and array of size 1000. I have to return SUBSET whose sum is the largest possible but not greater than M. Naturally, I wanted to code it like coin change or knapsack, but it fails in either memory or time. Any ideas?

FOUND IT: They actually gave me a problem from Google HashCode... It doesn't have even a valid solution, only one to approximate. I told them it's not possible to solve it in these constraints, they told me I should come up with a solution... Shame on you GSA Capital!

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By alex_ita, history, 5 years ago, In English

Hi everyone. I've been struggling to solve this task for a longer period of time now. I've read the official code, but still I don't understand what it does. So, if anyone can help me, I would be very thankful...

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By alex_ita, history, 6 years ago, In English

Hi everyone. I was just searching for editorial of some round on Google, found what I was searching for, and it opened a page that looks exactly the same as the Codeforces' page. I saw I was logged off, and I found it a bit odd, but I thought my 1-month session passed, so I tried to log in again, got an error, and then I realized... that link was nowhere near codeforces.com. So now I'm worried about is that a phishing website or not.
Here is the link.

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By alex_ita, history, 6 years ago, In English

Hello everyone!
I've recently learned Suffix array and how to build LCP array (using this code). I've solved a few problems, but then I found this one and couldn't solve it.
Can anyone help me how to solve Jarvis and LCP using that code?

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By alex_ita, history, 6 years ago, In English

Hello everyone!
As most of you know, you can downvote or upvote comments, blogs etc. However, many CF users tend to downvote comments/entries without a purpose, so you can see (what most of us know) a valid comment having e.g. 20 downvotes. What I'm thinking is, it could be fixed at least a bit.
For example, let's say 'Alex' comments on something. There comes 'Vasek' and downvotes Alex's comment. Then, there could be 2 improvements:
1) Out of all Vasek's votes, let's say at most 40% can be downvotes, else he can't downvote. There are lots of people who are striving to downvote most of the time. This would prevent them to "always" downvote.
2) Votes should NOT be to visible to 'Vasek' until he votes on that comment. That prevents other users to "automatically" downvote without even reading the comment, judging it just by the current votes.
3) Let's combine these 2 ideas into one. 'Vasek' doesn't see current votes on that comment. After 'Vasek' tries to downvote, if out of all of his votes, downvotes are 40% or more, he CAN'T downvote.

In addition:
-it might be a good idea NOT to allow unrated people, and/or people with contribution<=0 to vote
-people who downvoted too much (40% or whatever percentage you think is good) shouldn't be allowed to (down)vote for some period of time
-it should be possible to delete your comment whenever you want, but it's affection on your contribution stays the same.

I hope you agree with me, and some actions will be taken by MikeMirzayanov.

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By alex_ita, history, 6 years ago, In English

Hello everyone. I'm wondering if anyone knows on what date will IOI 2019 (in Azerbeijan) be held? Also, does anyone know any info (at least place) about Balkan Olympiad in Informatics 2019 (BOI) ?

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By alex_ita, history, 6 years ago, In English

Hey everyone!
Last year, there was an online mirror on @csacademy for both days of Balkan Olympiad in Informatics. I'm wondering if
anyone will do the same this year?

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