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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):       Vincent Rouvreau
 *
 *    Copyright (C) 2014 Inria
 *
 *    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 <gudhi/Simplex_tree.h>

#include <iostream>

using Simplex_tree = Gudhi::Simplex_tree<>;
using Simplex_handle = Simplex_tree::Simplex_handle;

int main(int argc, char* const argv[]) {
  // Construct the Simplex Tree with a 1-skeleton graph example
  Simplex_tree stree;

  stree.insert_simplex({0, 1}, 0.);
  stree.insert_simplex({0, 2}, 1.);
  stree.insert_simplex({0, 3}, 2.);
  stree.insert_simplex({1, 2}, 3.);
  stree.insert_simplex({1, 3}, 4.);
  stree.insert_simplex({2, 3}, 5.);
  stree.insert_simplex({2, 4}, 6.);
  stree.insert_simplex({3, 6}, 7.);
  stree.insert_simplex({4, 5}, 8.);
  stree.insert_simplex({4, 6}, 9.);
  stree.insert_simplex({5, 6}, 10.);
  stree.insert_simplex({6}, 10.);

  stree.expansion_with_blockers(3, [&](Simplex_handle sh) {
    bool result = false;
    std::cout << "Blocker on [";
    // User can loop on the vertices from the given simplex_handle i.e.
    for (auto vertex : stree.simplex_vertex_range(sh)) {
      // We block the expansion, if the vertex '6' is in the given list of vertices
      if (vertex == 6) result = true;
      std::cout << vertex << ", ";
    }
    std::cout << "] ( " << stree.filtration(sh);
    // User can re-assign a new filtration value directly in the blocker (default is the maximal value of boudaries)
    stree.assign_filtration(sh, stree.filtration(sh) + 1.);

    std::cout << " + 1. ) = " << result << std::endl;

    return result;
  });

  std::cout << "********************************************************************\n";
  std::cout << "* The complex contains " << stree.num_simplices() << " simplices";
  std::cout << "   - dimension " << stree.dimension() << "\n";
  std::cout << "* Iterator on Simplices in the filtration, with [filtration value]:\n";
  for (auto f_simplex : stree.filtration_simplex_range()) {
    std::cout << "   "
              << "[" << stree.filtration(f_simplex) << "] ";
    for (auto vertex : stree.simplex_vertex_range(f_simplex)) std::cout << "(" << vertex << ")";
    std::cout << std::endl;
  }

  return 0;
}