std::istream_iterator<T,CharT,Traits,Distance>::operator++, operator++(int)
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                    < cpp | iterator | istream iterator
                    
                                                            
                    |   istream_iterator& operator++();  | 
(1) | |
|   istream_iterator operator++(int);  | 
(2) | |
Reads a value from the underlying stream and stores it into the iterator object. If the read fails, the iterator becomes the end-of-stream iterator.
The behavior is undefined if the iterator is end-of-stream iterator.
Parameters
(none)
Return value
1) *this.
2) An 
istream_iterator that holds an unchanged value.Exceptions
(none)