abhinavsingh15682's blog

Accepted with C++17 but not with both C++20 and C++14
By abhinavsingh15682, history, 2 years ago, In English

While solving 1612C - Chat Ban I found something weird. I have submitted same code with C++14 and C++17,C++20. But it only was accepted with C++17.

C++14 :158761775

C++17 :158762654

C++20 :158762172

I tried to look for the reason online but could not find any.

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2 years ago, # |
  Vote: I like it +6 Vote: I do not like it

contact your local exorcist asap

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2 years ago, # |
  Vote: I like it -13 Vote: I do not like it

https://codeforces.net/contest/1612/submission/158779409

compare your solution with this modified solution of yours you will get it

or simply k*(k+1)/2 is not equal to (k*(k+1))/2

so in your code k*(k+1)/2 will give correct result if $$$k$$$ is $$$odd$$$ else it will give one less value then expected

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    2 years ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    i tried this code in custom test and it gives the correct result even if k is even.

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    2 years ago, # ^ |
      Vote: I like it +10 Vote: I do not like it

    I don`t think it`s the reason because the order of operator is defined in the standard of c++.

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2 years ago, # |
← Rev. 2   Vote: I like it +5 Vote: I do not like it

i think it is because of precision issues, i fixed it by adding (long double) inside the sqrt function: 158781091

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