oursaco's blog

By oursaco, history, 6 months ago, In English

did codeforces just remove c++11 from the compile languages

 
 
 
 
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6 months ago, # |
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Yes. We cannot submit codes in C++11. We could only submit C++14 or higher versions of C++.

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6 months ago, # |
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Topcoder disagree

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6 months ago, # |
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inb4 usaco removes c++11

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6 months ago, # |
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It's a interesting thing that China Computer Federation don't let competitors use c++11 as well.

They only let us use c++98 :(

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    6 months ago, # ^ |
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    Sad, Codeforces has removed C++11 but CCF still only let us use C++98 :(

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    5 months ago, # ^ |
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    Fun fact: In NOI Linux 1.4.1, which is still in use in NOI 2021, the gcc version is 4.8.4, which does not even fully support C++14 features.

    NOI is out of fashion

    Now that the GCC version has been updated to 9.3.0, let's pray that the CCF will allow the use of C++17 in future contests XD

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    5 months ago, # ^ |
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    Funny coincidence because less than 24 hours ago I was in a coding contest on VJudge and the compiler spat out Chinese error messages saying that stringstream could not be found and I spent 20 minutes debugging something only to find out that it used 16 bit ints which caused overflow.

    pain

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    5 months ago, # ^ |
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    98 > 11

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    5 months ago, # ^ |
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    There is a new system called NOI Linux 2.0. I wonder it let us use c++11 in NOI Linux 2.0 :) .

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    2 months ago, # ^ |
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    But now, CCF let us use C++14.

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5 months ago, # |
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deleted

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    5 months ago, # ^ |
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    Me who revised 4 times to see what the comment is

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5 months ago, # |
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Good.

I hope they add C++20 with GCC 11.2. There are many useful features there.

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    5 months ago, # ^ |
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    There are many useful features there.

    I only know of three-way comparision operator, default == operator and initializer in for-each loop. Kindly let us know if you know anything more that will be useful in CP.

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      5 months ago, # ^ |
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      Concepts, templated lambdas, std::ranges, std::span, and std::format sound like pretty useful features.

      std::midpoint will do away with a lot of midpoint related overflow/underflow issues, which is a good thing too.

      There's also a prefix and suffix comparison on strings, which will reduce the amount of code written for brute force string problems. Also, for containers like std::map and std::set, you will be able to check if an element exists using something like if (a.contains(element)), which would be better than the much more dangerous if (a.count(element)) which blows up to $$$O(frequency)$$$ for multisets.

      For some (warning: very rare) constant-factor optimization, [[likely]] and [[unlikely]] attributes would be a compiler-agnostic feature (no more using GCC's __builtin_expect anymore, so yay). Also as someone told me yesterday, C++20's [[no_unique_address]] can be useful for optimizing away empty structs.

      Use-case
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        5 months ago, # ^ |
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        Also everything in the <bit> header, no more ugly intrinsics.

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5 months ago, # |
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I've been using c++11 just because I already had it installed on my computer. Any recommendations on whether to upgrade to 14, 17, or directly to 20?

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    5 months ago, # ^ |
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    I would say C++17, it's a bit premature to upgrade to 20

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5 months ago, # |
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HackerRank.com has already included C++20 among its compiler options in the C++ practice problems section. Perhaps it is time for the Codeforces team to consider installing C++20.

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5 months ago, # |
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I am glad to use C++20 with GCC 11.2 here.