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Runtime Error while using comparator?
By NeutralMilkHotel, history, 4 years ago, In English

https://mirror.codeforces.com/contest/1148/submission/88665764 .Runtime error in https://mirror.codeforces.com/contest/1148/problem/D . I cannot figure out why there is runtime error, inspite of such low memeory being used. All the values are distinct in the problem.

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4 years ago, # |
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A C++ comparator must be a strict weak ordering. The three properties of a strict weak ordering is asymmetry, irreflexivity, and transitivity.

Asymmetry means that if $$$a < b$$$, then $$$b \not<a$$$.

Irreflexivity means $$$a<a$$$ is false.

Transitivity means if $$$a<b$$$ and $$$b<c$$$ then $$$a<c$$$.

Your comparator contradicts all three.

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