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WA (c++14) to AC (c++17), same code
By Jomax100, history, 5 years ago, In English

As the title suggests, I submitted the identical source code, which in my environment and in c++17 gives the right answer, but in c++14 it gives WA. I am aware this usually involves some sort of default initialization, but I believe my codes does not rely on that. I appreciate your help and insights as to what might be happening!

WA

AC

Two editorials for this problem, but I followed this one

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5 years ago, # |
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Auto comment: topic has been updated by Jomax100 (previous revision, new revision, compare).

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5 years ago, # |
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id[a[i].u] = sz(id);

It is not guaranteed that sz(id) will be evaluated before id[a[i].u], until C++17.
For more info: Order of evaluation

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5 years ago, # |
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You should write forn(h, sz(b)+1){ forn(u, sz(b)+1){ forn(v, sz(b)+1){ mmin(dp[u][v], dp[u][h] + dp[h][v]); } } } because your indexes are from 1 to sz(b),not 0 to sz(b)-1 After changing it got AC:57892426

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    5 years ago, # ^ |
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    Interesting fix. On my machine the ids started at 0. This must be the undefined behaviour mentioned by meooow

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