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FIICode Final Round [CSAcademy online mirror — rated]
By Juve45, history, 6 years ago, In English

The FIICode Final Round will take place Saturday, from 7AM to 10AM (UTC).

We will host an online mirror on CSAcademy at 10:05 (UTC). It will last 3 hours. We invite everyone to join.

Edit: mirror link The difficulty will be similar to a div 1 Codeforces contest. This round will be rated :)

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6 years ago, # |
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Auto comment: topic has been updated by Juve45 (previous revision, new revision, compare).

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6 years ago, # |
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Auto comment: topic has been updated by Juve45 (previous revision, new revision, compare).

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6 years ago, # |
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Rated contest in CSA :o

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6 years ago, # |
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The solutions have just been published, with extra bonus challenges.

Can you solve problem F's bonus challenge?

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6 years ago, # |
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Even though the editorial for E is simple, there is another easy solution to E (one with no edges cases);

We can treat this as a 1 player game for P1. For each removal of a $$$b$$$, P1 gets 1 point. After all operations, for each sequence of $$$X$$$ $$$a$$$'s, P1 loses $$$\lfloor X/3 \rfloor$$$ points. P1 wins iff the maximal amount of points he can get is positive.

We can solve with dp: $$$dp_{i, j}$$$ is the maximal amount of points P1 can get, if we only consider the prefix of length $$$i$$$, and the last sequence of $$$a$$$'s was of length $$$j$$$ (modulo 3). Transitions are easy in constant time.

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    6 years ago, # ^ |
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    That’s right. In fact, both our accepted solutions for E were done using this idea. (during the contest)

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6 years ago, # |
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i am unable to submit to the tasks on CSA since the contest has ended. does anyone else have the same issue?

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