std::multiset::key_comp
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|   key_compare key_comp() const;  | 
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Returns the function object that compares the keys, which is a copy of this container's constructor argument comp. It is the same as value_comp.
Parameters
(none)
Return value
The key comparison function object.
Complexity
Constant.
See also
|    returns the function that compares keys in objects of type value_type  (public member function)  |