Nocturnality's blog

By Nocturnality, 6 weeks ago, In English

Hello Codeforces!

I organized a contest at my university in November 2023, and I'm happy to welcome all of you to participate virtually or solve the problems later on.

Contest link: Intra Department Programming Contest, CSE-BU

There are 8 problems and 150 minutes to solve them. Problems are not sorted by difficulty order. I recommend you to read all the problems.

This problemset were create for users with a rating range from 0 to 1400 but anyone welcome to participate virtually or upsolve the problems!

I would like to thank everyone who was involved in the contest preparation:

I tried my best to keep the statements short and clear and I hope you will like the problemset!

Happy Coding!

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6 weeks ago, # |
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what's wrong with this

F WA 6
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    6 weeks ago, # ^ |
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    I used the exact same code but, for prefix, used an array instead of vector. Got AC.

    Code
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      6 weeks ago, # ^ |
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      Thanks! can you explain why using vector gives WA

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        6 weeks ago, # ^ |
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        It's actually not your fault. Constraints clearly show that 1 ≤ l, but test 6 actually has l less than 1. I tried using using .at() function instead of [] and got runtime error, while using pref[max(l — 1, 0)] passed.

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      6 weeks ago, # ^ |
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      forIoop Thanks for your help. I've sorted out the constraints and test cases, so everything should be fine now.

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    6 weeks ago, # ^ |
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    alpha1215 You have to consider the case when L=0.

    Unfortunately I missed the constraints (0 $$$\le$$$ L). Now I fixed it and everything alright.

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6 weeks ago, # |
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Nice contest, though I do feel it's still easier than regular Div.4.

Thoughts and feedbacks from an outsider
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    6 weeks ago, # ^ |
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    • This is my first setted contest in CF.
    • Most of the participants were freshman. That's why I had to do it and setted a problem like E.
    • I already fixed all of the constraints in the problemset.

    AkiLotus Thanks a lot for your valuable suggestions.

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6 weeks ago, # |
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Good Initiative.

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6 weeks ago, # |
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Thank you for setting this up, it was fun to do.

My short feedback would be
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5 weeks ago, # |
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why in C just sorting and returning square of min of 4 max elements gives WA on test 15