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In this non-compliant example, the IntSetLE type defines a set with less_equal specified as the ordering rule. Less than or equal is not a valid ordering rule because it violates the requirement to provide a "strict weak ordering" over the objects compared. In particular, this ordering rule fails to return false for equal values. As a result, the iterator pair returned by the equal_range() method are is inverted and the subsequent loop fails to terminate.
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