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Output iterator steps forward with write access and is provided by ostream and inserter

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Description

Output iterator moves forward and may store but not retrieve values, provided by ostream and inserter.

Output iterator allows you to assign new values only element-by-element. Therefore, we can't use an output iterator to iterate twice over the same range.

Note! No comparison operations are required for output iterators. You can't check if an output iterator is valid or if a "writing" was successful.

Operations

Expression	Description
*i=val	Writes val to where the iterator refers
++i	Steps forward and returns new position (when not null)
i++	Steps forward and returns old position (when not null)
TYPE(i)	Copies iterator (copy constructor)

References

http://www.tenouk.com/
Nicolai M. Josuttis: "The C++ Standard Library"

Example 1

Problem

The following example of program illustrates creation of a deque using output iterator.

Workings

#include <iostream>
using std::cout;
using std::endl;

#include <deque>     // deque class-template definition
#include <algorithm> // copy algorithm
#include <iterator>  // ostream_iterator

int main()
{
   std::deque< int > values; // create deque of type int
   std::ostream_iterator< int > output(cout, " ");

   values.push_front(2);
   values.push_front(3);
   values.push_back(1);

   cout << "values contains: ";
   // use subscript operator to obtain elements of values
   for ( int i = 0; i < values.size(); i++ )
      cout << values[i] << ' ';
   cout << endl;
   return 0;
}

Solution

Output:

values contains: 3 2 1

References

http://www.smu.ca/academic/science/compsci

Output Iterator

Description

Operations

References

Example 1

See Also