std::istream_iterator::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.
The behavior is undefined if the iterator is end-of-stream iterator.
[edit] Parameters
(none)
[edit] Return value
1) *this.
2) An 
istream_iterator that holds an unchanged value.[edit] Exceptions
(none)