Why Codechef does not make contest problems test cases public after contest gets over ?

@pshishod2645 bro, No one “wants to” post code on forums to find where code is failing but after trying to certain level(giving 200% percent) when one think now he cant do anything further, its good to ask on discuss forum to know whats wrong in previous approach rather than skipping that question or trying other approach


No its not infinite loops xD. Since each file only has a single TC, its very possible to get large variations over time. I faced that too. For me, TC 1 of task-3 was failing. Had to optimize my code :frowning:

@pshishod2645 its not compulsory to look at testCases… if one wants to try more he/she can try more without looking at test cases

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Making test cases public, well, to be honest small cases can help. It was an idea for my future editorials to keep a testcase bank (couldnt do it in ltime60 due to lack of time to analyze solutions).

We cannot force codechef to reveal them, and more often than not they are maximal cases with N=1000 in smaller ones and N={10}^{5} in larger ones.

@vijju123, What if the editorial includes a link to the test files? The test files will hardly exceed 6MB in size. Once downloaded, it’ll be upto the users whether they want to wait until “Notepad” responds, or they want to keep trying to find out the corner case without it…XD


@sarthakmanna for me its good Idea

He is talking about making them public after contest so the analogy of ACM ICPC doesn’t hold valid. Besides, in codeforces you can see the testcase for which your code fails after the contest and it is very helpful in practice. The suggestion to do the same on codechef is a very valid one.

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@sarthakmanna - Its essentially revealing the test cases at the end of the day. While I agree that one can put in corner cases there, I doubt that codechef will agree to reveal all the test cases. Its something the team is very particular about.

Larger ones are not revealed by CF fully. Smaller edge cases can be put up by editorialist. That can be done, but it needs analysis of what contestants are doing to figure out what can be corner cases for various approaches.


I agree editorialist can do that nicely… but with help of problem setter and tester the “public test cases” can be made of excellent quality… And they ll be more useful…

PS: Adding some corner test cases on editorial is a very good idea…

Though I also agree with @admin to not to reveal whole test case file as finding your own mistakes is kind of “fun” and a “skill”… Initially I was also frustrated and many people even get frustrated due to not revealing test cases in every contest… But after sometime I enjoyed that…
And in fact now I have hardly any question which was not submitted and got AC even after knowing logic properly… I learnt how to write neat bug free codes… And that is a skill I aquired by codechef…

And even I don’t get TLE’s due to lack of minor optimizations… If I got logic then AC is for sure… though it may take sometime… For eg. In VSN I got many wrong answers due to lack of practice in handling large double values… so eventually “not revealing” also helps…
#but as suggested by @vijju123 the idea to post some small corner cases in editorial is very good… And even it don’t reveal the whole test cases file and spoil the fun of debugging…

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That is when u need help of other solutions or ur friends or discuss… If it would be easily available then everyone will give up earlier… ik it’s upto us but then too if it was easily available then why a “beginner” will go for debugging…

Why wouldn’t a beginner go for debugging? Anybody who wants to learn to solve problems in contest will try to learn it. On the other hand if we know test cases we can at least still learn the concept instead of giving up.

The giving up one is a valid point. But more often than not, such cases are very specific to the approach you employed. A common bank may be hard to accommodate this.

Regarding revealing all test cases, most of the people (especially newcomers) arent disciplined enough to know how to use that. This move will do more harm as they will have poor debugging skills leading to poor performance in contest and demotivation.

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Yes, editorialist will take setter and tester’s help only xD. But mostly there are cases which may or may not be “corner cases” depending on your approach. For that, analysis of solution is required.

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Exactly that was my point @vijju123… They aren’t disciplined enough…

If u give some students a “copy chit” in exam and ensure that they won’t be punished then many of them will take it… they won’t think about themselves… that’s why people keep supervisor even in practice tests…

Then people will share test cases by making fake submission… which isbnot desirable… U can always ask for help to people after lot of efforts from you… Many people can help u with that actually if ur soln is neat enough and u did tried properly to get answer before asking