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diff --git a/src/Coxeter_triangulation/include/gudhi/Permutahedral_representation/Combination_iterator.h b/src/Coxeter_triangulation/include/gudhi/Permutahedral_representation/Combination_iterator.h
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+/* This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
+ * See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
+ * Author(s): Siargey Kachanovich
+ *
+ * Copyright (C) 2019 Inria
+ *
+ * Modification(s):
+ * - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef PERMUTAHEDRAL_REPRESENTATION_COMBINATION_ITERATOR_H_
+#define PERMUTAHEDRAL_REPRESENTATION_COMBINATION_ITERATOR_H_
+
+#include <vector>
+#include <boost/range/iterator_range.hpp>
+
+namespace Gudhi {
+
+namespace coxeter_triangulation {
+
+typedef unsigned uint;
+
+/** \brief Class that allows the user to generate combinations of
+ * k elements in a set of n elements.
+ * Based on the algorithm by Mifsud.
+ */
+class Combination_iterator
+ : public boost::iterator_facade<Combination_iterator, std::vector<uint> const, boost::forward_traversal_tag> {
+ typedef std::vector<uint> value_t;
+
+ protected:
+ friend class boost::iterator_core_access;
+
+ bool equal(Combination_iterator const& other) const { return (is_end_ && other.is_end_); }
+
+ value_t const& dereference() const { return value_; }
+
+ void increment() {
+ if (value_[0] == n_ - k_) {
+ is_end_ = true;
+ return;
+ }
+ uint j = k_ - 1;
+ if (value_[j] < n_ - 1) {
+ value_[j]++;
+ return;
+ }
+ for (; j > 0; --j)
+ if (value_[j - 1] < n_ - k_ + j - 1) {
+ value_[j - 1]++;
+ for (uint s = j; s < k_; s++) value_[s] = value_[j - 1] + s - (j - 1);
+ return;
+ }
+ }
+
+ public:
+ Combination_iterator(const uint& n, const uint& k) : value_(k), is_end_(n == 0), n_(n), k_(k) {
+ for (uint i = 0; i < k; ++i) value_[i] = i;
+ }
+
+ // Used for the creating an end iterator
+ Combination_iterator() : is_end_(true), n_(0), k_(0) {}
+
+ void reinitialize() {
+ if (n_ > 0) {
+ is_end_ = false;
+ for (uint i = 0; i < n_; ++i) value_[i] = i;
+ }
+ }
+
+ private:
+ value_t value_; // the dereference value
+ bool is_end_; // is true when the current permutation is the final one
+
+ uint n_;
+ uint k_;
+};
+
+} // namespace coxeter_triangulation
+
+} // namespace Gudhi
+
+#endif