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Problem with Codeforces C++ 11 compiler?
By tenshi_kanade, history, 9 years ago, In English

I've recently come across a very strange problem using C++ 11.

I submitted a solution for problem 620C - Pearls in a Row using unordered_map and got TLE, then I submitted the exact same solution using map (it's supposed to be slower: O(1) amortized VS O(logN) per operation) and it got Accepted with 280 ms.

Submission with unordered_map: 15756653

Submission with map: 15759645

Is this some kind of problem with the C++11 compiler used here on Codeforces? Anyone got a clue?

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9 years ago, # |
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Auto comment: topic has been updated by tenshi_kanade (previous revision, new revision, compare).

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9 years ago, # |
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Looking at the different execution times, for both submissions, unordered_map seems to be faster, maybe that particular case is antihashing and a lot of collisions happen? That could explain the TLE

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9 years ago, # |
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http://codeforces.net/blog/entry/22947?#comment-274056

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