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// Copyright (c) 1997
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel). All rights reserved.
//
// This file is part of CGAL (www.cgal.org)
//
// $URL: https://github.com/CGAL/cgal/blob/v6.1/Generator/include/CGAL/random_selection.h $
// $Id: include/CGAL/random_selection.h b26b07a1242 $
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
//
// Author(s) : Lutz Kettner <kettner@inf.ethz.ch>
#ifndef CGAL_RANDOM_SELECTION_H
#define CGAL_RANDOM_SELECTION_H 1
#include <cstddef>
#include <iterator>
#include <CGAL/Random.h>
namespace CGAL {
template <class RandomAccessIterator, class Size, class OutputIterator,
class Random>
OutputIterator random_selection( RandomAccessIterator first,
RandomAccessIterator last,
Size n,
OutputIterator result,
Random& rnd)
// choose a random item from the range [`first',`last') and write it
// to `result', each item from the range with equal probability.
// Repeat this n times, thus writing n items to `result'. A single
// random number is needed from `rnd' for each item. Returns the
// value of `result' after inserting the n items.
{
std::ptrdiff_t m = last - first;
for ( Size i = 0; i < n; i++) {
*result++ = first[ rnd(m)];
}
return result;
}
template <class RandomAccessIterator, class Size, class OutputIterator>
OutputIterator random_selection( RandomAccessIterator first,
RandomAccessIterator last,
Size n,
OutputIterator result)
{
return random_selection( first, last, n, result, get_default_random());
}
} //namespace CGAL
#endif // CGAL_RANDOM_SELECTION_H //
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