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diff --git a/src/Witness_complex/example/witness_complex_from_file.cpp b/src/Witness_complex/example/witness_complex_from_file.cpp
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+++ b/src/Witness_complex/example/witness_complex_from_file.cpp
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+/*    This file is part of the Gudhi Library. The Gudhi library
+ *    (Geometric Understanding in Higher Dimensions) is a generic C++
+ *    library for computational topology.
+ *
+ *    Author(s):       Siargey Kachanovich
+ *
+ *    Copyright (C) 2015  INRIA Sophia Antipolis-Méditerranée (France)
+ *
+ *    This program is free software: 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.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <gudhi/Points_off_io.h>
+#include <gudhi/Simplex_tree.h>
+#include <gudhi/Witness_complex.h>
+#include <gudhi/Construct_closest_landmark_table.h>
+#include <gudhi/pick_n_random_points.h>
+#include <gudhi/reader_utils.h>
+
+#include <iostream>
+#include <fstream>
+#include <ctime>
+#include <string>
+#include <vector>
+
+typedef std::vector< Vertex_handle > typeVectorVertex;
+typedef std::vector< std::vector <double> > Point_Vector;
+
+int main(int argc, char * const argv[]) {
+  if (argc != 3) {
+    std::cerr << "Usage: " << argv[0]
+        << " path_to_point_file.off nbL \n";
+    return 0;
+  }
+
+  std::string off_file_name = argv[1];
+  int nbL = atoi(argv[2]);
+  clock_t start, end;
+
+  // Construct the Simplex Tree
+  Gudhi::Simplex_tree<> simplex_tree;
+
+  // Read the OFF file (input file name given as parameter) and triangulate points
+  Gudhi::Points_off_reader<std::vector <double>> off_reader(off_file_name);
+  // Check the read operation was correct
+  if (!off_reader.is_valid()) {
+    std::cerr << "Unable to read file " << off_file_name << std::endl;
+  }
+  // Read the point file
+  Point_Vector point_vector = off_reader.get_point_cloud();
+  std::cout << "Successfully read " << point_vector.size() << " points.\n";
+  std::cout << "Ambient dimension is " << point_vector[0].size() << ".\n";
+
+  // Choose landmarks
+  start = clock();
+  std::vector<std::vector< int > > knn;
+  Point_Vector landmarks;
+  Gudhi::subsampling::pick_n_random_points(point_vector, 100, std::back_inserter(landmarks));
+  Gudhi::witness_complex::construct_closest_landmark_table(point_vector, landmarks, knn);
+  end = clock();
+  std::cout << "Landmark choice for " << nbL << " landmarks took "
+      << static_cast<double>(end - start) / CLOCKS_PER_SEC << " s. \n";
+
+  // Compute witness complex
+  start = clock();
+  Gudhi::witness_complex::witness_complex(knn, nbL, point_vector[0].size(), simplex_tree);
+  end = clock();
+  std::cout << "Witness complex took "
+      << static_cast<double>(end - start) / CLOCKS_PER_SEC << " s. \n";
+}