Everule's blog

By Everule, history, 2 years ago, In English

Disclaimer : I just want to highlight some simple techniques used to solve Ad-Hoc tasks.

In my opinion, these are all simple techniques, but a lot of these are used even in much harder problems. I hope these will be helpful to some people.

1: Eliminate obvious cases, and see if you can simplify the problem.

Solution

2: Ignore unnecessary information, and use it to draw the problem in new ways.

Solution

3: Making obvious lower and upper bounds, and proving they are constructible.

Solution

4: Finding invariants

Solution

5 : Define something that cannot change much.

Solution
Question that uses many of these
Solution
 
 
 
 
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2 years ago, # |
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What's Ad-Hoc tasks?

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    2 years ago, # ^ |
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    An Ad-Hoc task is something that doesn't fit into any specific topic. These are questions whose solution you have to come up with completely by yourself.

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      2 years ago, # ^ |
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      Ad-Hoc seems like a abbreviation,is it?

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        2 years ago, # ^ |
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        Ad-Hoc is actually a Latin phrase, that means "to this"

        Google phrases it better :

        In English, it generally signifies a solution designed for a specific problem or task, non-generalizable, and not intended to be adapted to other purposes.

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2 years ago, # |
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great post with perfect examples.

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2 years ago, # |
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omg thank you for this everule <3

I hope you reach LGM soon!

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2 years ago, # |
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Nice blog!

Suggestion: Try to include the abridged problem statement within the blog for uninterrupted readability.

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    2 years ago, # ^ |
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    I'm OK without the abridged problem statements, because part of the skill is reading the problem statement and understanding the core idea (and especially people who read this blog because they struggle with As and Bs can probably benefit from practicing this skill).

    I would say there's no reason to put the problem link in a spoiler block, though, since it's only 1 word/line anyway.

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      2 years ago, # ^ |
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      I just meant it in the sense that it's a little inconvenient to switch tabs repeatedly while reading a blog.

      And yes I agree that there was no reason to put it in the spoiler block, but I didn't point it out because it's not a big issue anyway.

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2 years ago, # |
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I think instead of "question", "problem" or "task" are more appropriate here.

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2 years ago, # |
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Thanks for sharing the resource. I will try to use these methods!

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2 years ago, # |
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Congrats on reaching red! That was fast! orz

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7 months ago, # |
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Why is problem 3 adhoc? This seems to be easily noticeable DP+Trees(https://codeforces.com/contest/1436/submission/163778824) problem.