std::unordered_map::at
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                    < cpp | container | unordered map
                    
                                                            
                    
| T& at( const Key& key ); | (1) | (since C++11) | 
| const T& at( const Key& key ) const; | (2) | (since C++11) | 
Returns a reference to the mapped value of the element with key equivalent to key. If no such element exists, an exception of type std::out_of_range is thrown.
| Contents | 
[edit] Parameters
| key | - | the key of the element to find | 
[edit] Return value
Reference to the mapped value of the requested element
[edit] Exceptions
std::out_of_range if the container does not have an element with the specified key
[edit] Complexity
Average case: constant, worst case: linear in size.
[edit] See also
| access specified element (public member function) | 


