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Weak test cases for the problem C of Codeforces Round 664 (div 2)
By Sumarbrander, history, 4 years ago, In English

My solution for the problem 1395C - Boboniu и битовые операции of the contest Codeforces Round 664 (Div. 2) was uphacked by Lightbender after the contest. So I was looking for the same mistake in other participants' code and found another user with code giving the wrong output on the same test case. Thanks yellow_13 for finding the test case. I feel that many incorrect codes might have been accepted because of weak test cases.

My Submission:- 89709001

Other Submission:- 89699186

The solution fails for the test case

3 2

3 10 128

130 137

The output should be 130 but the code outputs 131. This is the second time in last 3 contests that incorrect codes have been accepted due to weak test cases. I ask the Codeforces community and sshwyR to look into it.

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Comments Comments (8)
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4 years ago, # |
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Auto comment: topic has been updated by Sumarbrander (previous revision, new revision, compare).

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4 years ago, # |
  Vote: I like it +8 Vote: I do not like it

Sorry for that:(

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    4 years ago, # ^ |
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    But this round gave a lot of wrong ratings to users who got AC in this problem even after submitting a wrong solution ..

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4 years ago, # |
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mine was not accepted, bro. :cry:

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    4 years ago, # ^ |
      Vote: I like it -9 Vote: I do not like it

    When I was generating datas, I couldn't imagine the strange solutions for this problem. So I didn't know how to generating strong datas :(

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      4 years ago, # ^ |
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      All right, friend. I didn't lose a rating because of that, I only found myself a little terrified when the wa 31 started to appear for everyone with the same solution.But, if I passed the question, I would become cyan again.

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      4 years ago, # ^ |
        Vote: I like it -11 Vote: I do not like it

      That's why multitest exists.

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4 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Need moar testers!

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