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diff --git a/include/gudhi_patches/CGAL/internal/Combination_enumerator.h b/include/gudhi_patches/CGAL/internal/Combination_enumerator.h
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+++ b/include/gudhi_patches/CGAL/internal/Combination_enumerator.h
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+// Copyright (c) 2009-2014 INRIA Sophia-Antipolis (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org).
+// You can redistribute it and/or modify it under the terms of the GNU
+// General Public License as published by the Free Software Foundation,
+// either version 3 of the License, or (at your option) any later version.
+//
+// Licensees holding a valid commercial license may use this file in
+// accordance with the commercial license agreement provided with the software.
+//
+// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+//
+// $URL$
+// $Id$
+//
+// Author(s)    : Samuel Hornus
+
+#ifndef CGAL_INTERNAL_COMBINATION_ENUMERATOR_H
+#define CGAL_INTERNAL_COMBINATION_ENUMERATOR_H
+
+#include <CGAL/basic.h>
+#include <vector>
+
+namespace CGAL {
+
+namespace internal {
+
+class Combination_enumerator
+{
+    // types and member data
+    typedef std::vector<int> Combination;
+    Combination combi_;
+    const int k_;
+    const int min_;
+    const int max_;
+    const int max_at_pos_0_;
+
+public:
+
+    // For generating all the combinations of |k| distinct elements in the
+    // interval [min, max] (both included)
+    Combination_enumerator(const int k, const int min, const int max)
+    : combi_(k), k_(k), min_(min), max_(max), max_at_pos_0_(max + 1 - k)
+    {
+        CGAL_assertion_msg( min <= max, "min is larger than max");
+        CGAL_assertion_msg( 1 <= k && k <= ( max - min + 1 ), "wrong value of k");
+        init();
+    }
+    
+    Combination_enumerator(const Combination_enumerator & c)
+    : combi_(c.combi_), k_(c.k_), min_(c.min_), max_(c.max_), max_at_pos_0_(c.max_at_pos_0_)
+    {}
+
+    int number_of_elements()
+    {
+        return k_;
+    }
+
+    void init()
+    {
+        combi_.resize(k_);
+        for( int i = 0; i < k_; ++i )
+            element(i) = min_ + i;
+    }
+
+    bool end() const
+    {
+        return ( element(0) > max_at_pos_0_ );
+    }
+
+    int element(const int i) const
+    {
+        CGAL_assertion( 0 <= i && i < k_ );
+        return combi_[i];
+    }
+
+    int & element(const int i)
+    {
+        CGAL_assertion( 0 <= i && i < k_ );
+        return combi_[i];
+    }
+
+    int operator[](const int i) const
+    {
+        return element(i);
+    }
+
+    int & operator[](const int i)
+    {
+        return element(i);
+    }
+
+    void operator++()
+    {
+        int i = k_ - 1;
+        int max_at_pos_i(max_);
+        while( ( i >= 0 ) && ( element(i) >= max_at_pos_i ) )
+        {
+            --i;
+            --max_at_pos_i;
+        }
+        if( -1 == i )
+        {
+            if( element(0) == max_at_pos_0_ )
+                ++element(0); // mark then end of the enumeration with an impossible value
+            // Note than when we have arrived at the end of the enumeration, applying
+            // operator++() again does not change anything, so it is safe to
+            // apply it too many times.
+        }
+        else
+        {
+            ++element(i);
+            for( int j = i + 1; j < k_; ++j )
+                element(j) = element(i) + j - i;
+        }
+    }
+
+    Combination_enumerator operator++(int)
+    {
+        Combination_enumerator tmp(*this);
+        ++(*this);
+        return tmp;
+    }
+
+    // - - - - - - - - - - - - - - - - - - - - - - - - - - - TESTING
+#if 0
+    void test()
+    {
+        std::cerr << '\n';
+        while( ! end() )
+        {
+            std::cerr << '\n';
+            for( int i = 0; i < k_; ++i )
+                std::cerr << element(i) << ' ';
+            ++(*this);
+        }
+        init();
+    }
+#endif
+};
+
+} // end of namespace internal
+
+} // end of namespace CGAL
+
+#endif // CGAL_INTERNAL_COMBINATION_ENUMERATOR_H