std::unordered_map::erase
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                    < cpp | container | unordered map
                    
                                                            
                    
|   iterator erase( const_iterator pos );  | 
(1) | (since C++11) | 
|   iterator erase( const_iterator first, const_iterator last );  | 
(2) | (since C++11) | 
|   size_type erase( const key_type& key );  | 
(3) | (since C++11) | 
Removes specified elements from the container.
1) Removes the element at 
pos.2) Removes the elements in the range 
[first; last).3) Removes all elements with the key value 
key.References and iterators to the erased elements are invalidated. Other iterators and references are not invalidated.
Contents | 
[edit] Parameters
| pos | - | iterator to the element to remove | 
| first, last | - | range of elements to remove | 
| key | - | key value of the elements to remove | 
[edit] Return value
1-2) Iterator following the last removed element.
3) Number of elements removed.
[edit] Exceptions
1,2) (none)
3) Any exceptions thrown by the 
Compare object.[edit] Notes
The iterator pos must be valid and dereferenceable. Thus the end() iterator (which is valid, but is not dereferencable) cannot be used as a value for pos.
[edit] Complexity
Given an instance c of unordered_map:
1) Average case: constant, worst case: c.size()
3) Average case: c.count(key), worst case: c.size()
[edit] See also
|    clears the contents   (public member function)  | |