Problem 281. Acid and water

Created by AMITAVA BISWAS

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1172 Solutions
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Last Solution submitted on Apr 27, 2023

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PeterB on 17 Oct 2017

It makes no sense to speak of the mixture being part acid and part water. In fact the quantity of water is always 100, and the acid has a certain strength. It would have been better to get us to calculate the acid strength

Stephen Cohen on 19 Oct 2017

Needs more test cases to disqualify the non-solutions that simply exploit the test-case space.

David Verrelli on 31 Oct 2017

More test cases in the Test Suite is generally welcome, and also the threat of potentially adding (even) more cases in the future can deter hard-coded "non-solutions".

li haitao on 29 Oct 2018

Most the leading solutions are just overfit the test cases, and meaningless.

Rafael S.T. Vieira on 6 Jul 2020

This problem seems weird, I've solved the last test with hacking after using harmonic mean for the others, because I've imagined the speed was constant. However, people who solved without a hack acted as the speed was decreasing. And that doesn't make sense to me (it is not written at the problem description). The problem description IMHO needs to be changed if that's what the author was aiming. If you are reading this before trying to solve it, please, think about exponential decay. It is not linear despite the problem not saying so. Without this previous sentence, one may lose time trying several different solutions (like some people did in the solution set) or just hack it instead of learning something new (just point people at the right direction; they still can try some other technique if they want). Especially since the goal in Cody is to create a small solution.

Rafael S.T. Vieira on 6 Jul 2020

And I agree that more test cases should be added, besides improving its description. In Cody, there are broken tests. So we can never be sure at times wether our code or the test set is bogus.

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Problem 281. Acid and water

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