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.. Copyright David Abrahams 2006. Distributed under the Boost
.. Software License, Version 1.0. (See accompanying
.. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Example
.......
This example fills an array with numbers and a second array with
pointers into the first array, using ``counting_iterator`` for both
tasks. Finally ``indirect_iterator`` is used to print out the numbers
into the first array via indirection through the second array.
::
int N = 7;
std::vector<int> numbers;
typedef std::vector<int>::iterator n_iter;
std::copy(boost::counting_iterator<int>(0),
boost::counting_iterator<int>(N),
std::back_inserter(numbers));
std::vector<std::vector<int>::iterator> pointers;
std::copy(boost::make_counting_iterator(numbers.begin()),
boost::make_counting_iterator(numbers.end()),
std::back_inserter(pointers));
std::cout << "indirectly printing out the numbers from 0 to "
<< N << std::endl;
std::copy(boost::make_indirect_iterator(pointers.begin()),
boost::make_indirect_iterator(pointers.end()),
std::ostream_iterator<int>(std::cout, " "));
std::cout << std::endl;
The output is::
indirectly printing out the numbers from 0 to 7
0 1 2 3 4 5 6
The source code for this example can be found `here`__.
__ ../example/counting_iterator_example.cpp
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