std::reverse_iterator<Iter>::operator[]
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                    < cpp | iterator | reverse iterator
                    
                                                            
                    
|   /*unspecified*/ operator[]( difference_type n ) const;  | 
(until C++17) | |
|   constexpr /*unspecified*/ operator[]( difference_type n ) const;  | 
(since C++17) | |
Returns a reference to the element at specified relative location.
Parameters
| n | - | position relative to current location. | 
Return value
A reference to the element at relative location, that is, base()[-n-1].
Examples
| This section is incomplete Reason: no example  | 
See also
|    accesses the pointed-to element  (public member function)  |