Abdelaleem_Ahmed's blog

[GYM] Invitation to Shorouk Academy 2024 Collegiate Programming Contest
By Abdelaleem_Ahmed, 8 months ago, In English

Hello, codeforces community!

I am happy to invite you to participate in Shorouk Academy 2024 Collegiate Programming Contest that will held at Shorouk Academy. The online training will be on codeforces gyms and will start on Saturday, April 27, 2024 at 11:00 EEST.

The unofficial contest will take place in Codeforces Gym, following standard ICPC rules where individual and team participation are allowed. The contest is unrated and will last for 5 hours, featuring 13 problems.

The problems are written and prepared by only me — Abdelaleem_Ahmed.

Thanks to khepri, SalahSalem, HitmanX97, AbdalrhmanEssam, 3zim, Eslam_Ahmed, Abwbkr, OMAR_TAHA, ipy_, Ahmed_Dyab, Dr.rabi3, Glitch00, A7md_Roshdy, AhmedEhab, --ALPHA-- for solo testing.

Thanks to Shorouk Academy for hosting the onsite contest.

Thanks to Polygon for providing the amazing platform for creating and preparing the problems, and to codeforces for the hosting of the online training.

I hope you enjoy solving the problems. Any feedback will be appreciated.

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8 months ago, # |
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where is the editorial ?

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8 months ago, # |
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The editorial !

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8 months ago, # |
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The editorial !

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8 months ago, # |
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How to solve C ?

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    7 months ago, # ^ |
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    Binary Indexed Tree (2D)

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      2 months ago, # ^ |
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      Can you please explain your solution? We can't make 2D vector for the BIT! then how to solved it using 2D BIT?

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8 months ago, # |
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Editorial?

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    8 months ago, # ^ |
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    bit2d

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      3 months ago, # ^ |
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      Can you explain a little bit, how you applied BIT in it?

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        3 months ago, # ^ |
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        you can think of every pair (a_i, b_i) as a point in the coordinate plane. to not think a lot about coordinate compression you can just stick bit2d into it. Talking about question C

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          3 months ago, # ^ |
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          Thank's!

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          2 months ago, # ^ |
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          But we can't declare a 2D vector of size [n][n] to make the 2D bit, since n is upto 1e5, then how we can do it using 2D bit ? Can you please explain a bit more ?

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            2 months ago, # ^ |
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            a BIT2D doesn't just consist of n BITs. it works a bit differently and I can't explain better than tutorials on codeforces.

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