std::unordered_set::count
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                    < cpp | container | unordered set
                    
                                                            
                    
| size_type count( const Key& key ) const; | (1) | (since C++11) | 
Returns the number of elements with key that compares equal to the specified argument key, which is either 1 or 0 since this container does not allow duplicates.
| Contents | 
[edit] Parameters
| key | - | key value of the elements to count | 
[edit] Return value
Number of elements with key key, that is either 1 or 0.
[edit] Complexity
Constant on average, worst case linear in the size of the container.
[edit] See also
| finds element with specific key (public member function) | |
| returns range of elements matching a specific key (public member function) | 


