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In this noncompliant code example, the objects stored in the std::set have an overloaded operator< implementation, allowing the objects to be compared with std::less. However, the comparison operation does not provide a strict weak ordering. Specifically, the values 1, N and 1, M can two sets x and y, whose I values are both 1, but have differing j values can result in a situation where comp(x, y) == and comp(y, x) are both false, failing the asymmetry requirements.
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