Mahfuz2411's blog

B. Bobritto Bandito: Logical Flaw or Validator Bug?
By Mahfuz2411, history, 17 months ago, In English

Update: uphacked, thank you satyam343

Contest: Codeforces Round 1017 (Div. 4)
Problem: 2094B - Bobritto Bandito

Please read my post, and if you dislike it, kindly leave a comment explaining why you didn't like it before downvoting!

In this problem, for this test case: 

1
4 1 -2 2

The answer should be -1 0 or 0 1. However, this solution ( 315684773 ) gives -2 -1 for this test. Here is the screenshot: (https://prnt.sc/OvZ5SdwdoRq4 ), I tested it in Custom Invocation.

If I am correct, then how can CF accept this solution?

If I am wrong, please explain, and I will delete this post!

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17 months ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

Proof_by_QED

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17 months ago, hide # |
← Rev. 2  
Vote: I like it 0 Vote: I do not like it

Well spotted. This is a logical flaw with the solution which just wasn't caught by any of the pretests or hacks. Hopefully someone >=1900 in rating will come along and uphack it, but this will not affect his standings in the contest.

The checker is correct.

Update: uphacked, thank you satyam343

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