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diff --git a/src/GudhUI/utils/Lloyd_builder.h b/src/GudhUI/utils/Lloyd_builder.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):       David Salinas
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef UTILS_LLOYD_BUILDER_H_
+#define UTILS_LLOYD_BUILDER_H_
+
+#include <vector>
+#include <list>
+
+/**
+ * Iteratively puts every vertex at the center of its neighbors
+ */
+template<typename SkBlComplex> class Lloyd_builder {
+ private:
+  SkBlComplex& complex_;
+  int dim;
+
+ public:
+  typedef typename SkBlComplex::Vertex_handle Vertex_handle;
+
+  /**
+   * @brief Modify complex to be the expansion of the k-nearest neighbor
+   * symetric graph.
+   */
+  Lloyd_builder(SkBlComplex& complex, unsigned num_iterations) : complex_(complex), dim(-1) {
+    if (!complex_.empty()) {
+      dim = get_dimension();
+      while (num_iterations--) {
+        std::list<Point> new_points;
+        for (auto v : complex.vertex_range())
+          new_points.push_back(barycenter_neighbors(v));
+
+        auto new_points_it = new_points.begin();
+        for (auto v : complex.vertex_range())
+          complex_.point(v) = *(new_points_it++);
+      }
+    }
+  }
+
+ private:
+  int get_dimension() {
+    assert(!complex_.empty());
+    for (auto v : complex_.vertex_range())
+      return complex_.point(v).dimension();
+    return -1;
+  }
+
+  Point barycenter_neighbors(Vertex_handle v) const {
+    if (complex_.degree(v) == 0)
+      return complex_.point(v);
+
+    std::vector<double> res(dim, 0);
+    unsigned num_points = 0;
+    for (auto nv : complex_.vertex_range(v)) {
+      ++num_points;
+      const Point& point = complex_.point(nv);
+      assert(point.dimension() == dim);
+      for (int i = 0; i < point.dimension(); ++i)
+        res[i] += point[i];
+    }
+    for (auto& x : res)
+      x /= num_points;
+    return Point(dim, res.begin(), res.end());
+  }
+
+  double squared_eucl_distance(const Point& p1, const Point& p2) const {
+    return Geometry_trait::Squared_distance_d()(p1, p2);
+  }
+};
+
+#endif  // UTILS_LLOYD_BUILDER_H_