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# UASEQ - Editorial

 5 I still can't understand the solution. Can someone please explain it, preferably with an example? answered 17 Sep '14, 20:08 139●2●3●8 accept rate: 0%
 4 I even wrote a mail, commented on a forum post that the test cases are weak you should rejudge and all but they did not. i guess they got too lazy this time. For everyone thinking why the test cases are weak. you should try this: 3 1 1 4 5 Ans should be 1 3 5(common diff = 2) but every one whose output is 1 4 7 are wrong as common difference is 3 in the latter case. Acc to statement we were supposed to minimze 'd' if 'a'(lowest) is same. answered 15 Sep '14, 20:29 4★dcod 358●1●5●11 accept rate: 27% good work @dcod , I think the problem tester needs to look into this matter. @xcwgf666 (15 Sep '14, 23:29) Yes, we agree that this should be fixed. (01 Oct '14, 21:56) admin ♦♦0★
 2 Can anyone tell why there can be only K^2 variations in the candidate AP's and not N^N ? answered 16 Sep '14, 03:39 24●1●3 accept rate: 0%
 2 Well I dont think that writing tough test cases is a big problem. When you sit in a group of 10 people, you try to read the problem and try to think that what are all the different ways in which the problem can be misunderstood and give an appropriate counter-example. Then, even if some 'wrong' solutions getting AC are reported, then you should not hesitate from adding tougher test cases, as no one would like a wrong solution be considered as accepted. In the past few contests I have observed this weak tests problem a lot. I think we would get nowhere if we just solve the problem the way we like and you give AC and make us feel happy. Further it is a ten day long contest and no one should mind the addition of tough test cases as you are still left with considerable time to retry (compare 2 or 5 hour contests). Also it should be a duty of testers to frequently go through the accepted solutions and try to challenge/hack them and add those cases for all solutions (and you may call the system as Dynamic Solution Testing System) and rejudge all at the end. At the end of the day, correct solutions will pass all the test cases, no matter how they (solutions as well as cases) are generated. answered 24 Sep '14, 15:55 5★yash_15 518●1●7●16 accept rate: 2% Great...so u want 9-10k solutions(maybe more) to be read and challenged by a few testers...now that is a practical solution..:\ (24 Sep '14, 19:27) kunal3614★ which problem has 9-10k accepted solutions?? Moreover only some random solutions need to be seen. Further if you see the example above by @dcod, you should realise that the test cases were useless! This was a trivial thing that deserved a few test cases. I wont accept the point that testers could not think of this. (29 Sep '14, 16:07) yash_155★
 1 I tried this problem one day before contest end. My solution is O(n) and one more this it does not depend on K because of very week test cases. Even my solution was unable to pass the sample test case But AC because of small value of K. I never used K in my solution. Explanation of my algorithm -->it finds the longest contiguous AP sequence with start and end index in O(n) and the two loops one is from start to 0 and other is end to n. link to my solution http://www.codechef.com/viewplaintext/4822024 answered 15 Sep '14, 18:05 44●3 accept rate: 0% LMAO dude, even I thought of such a hack but I was implementing it the longer way around. Damn! (15 Sep '14, 19:54) same story --^-- (16 Sep '14, 03:45)
 1 What has happened here is unfortunate. We, as admins, admit that there were mistakes in the problem that could and should have been avoided or corrected when brought to the fore. This is an undesirable situation. We have spoken to our problem setting panel and there is no disagreement on this any more. What has happened in the contest cannot be undone and we regret that. We have requested the problem setter and the tester to fix the test data by adding many more test cases and make the test cases stronger in the practice section. However, we must understand and appreciate the effort and the pain it takes to make a problem and to test it, especially since the panel members have other academic/professional commitments as well. We will also try and make sure that the communication from our end to the panel happens clearly and there is no ambiguity on this any more. This should not happen again. We apologise for this incident. answered 01 Oct '14, 21:53 0★admin ♦♦ 19.8k●350●498●541 accept rate: 36%
 0 i kept thinking that there exists some DP solution for it until yesterday i saw that k is quite small and then i got the answer. answered 15 Sep '14, 17:18 3★defacto 23●1●2 accept rate: 0%
 0 Could anyone please elaborate on the brute force technique answered 15 Sep '14, 17:34 5★japoorv 295●9●23●56 accept rate: 0%
 0 Can someone please explain the brute force method mentioned in the editorial? answered 15 Sep '14, 20:57 26●2 accept rate: 0% Since we cannot change more than 'k' elements the last element(read maximum) has to be one of the last 'k' (read maximum 'k' elements of the list). Same holds true for first element. (19 Sep '14, 17:05)
 0 If I brute force first and last element of sequence which will not change, won't there be O(N*N) variants? answered 17 Sep '14, 23:51 1 accept rate: 0%
 0 You say that we should fix L and R, but in the example we change L. Why isn't that a contradiction? Also, what implies that L < R? And also, can't I make an example with a result with infinities? (if K >= N - 1)? answered 20 Sep '14, 08:10 11●1 accept rate: 0%
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question asked: 15 Sep '14, 15:47

question was seen: 6,108 times

last updated: 28 Oct '16, 16:46