complement.hh

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// This file is part of Awali.
// Copyright 2016-2022 Sylvain Lombardy, Victor Marsault, Jacques Sakarovitch
//
// Awali is a 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/>.
 
#ifndef AWALI_ALGOS_COMPLEMENT_HH
# define AWALI_ALGOS_COMPLEMENT_HH
 
# include <set>
 
#include <awali/sttc/algos/copy.hh>
#include <awali/sttc/algos/is_complete.hh>
#include <awali/sttc/algos/determinize.hh>
#include <awali/sttc/misc/raise.hh>
#include <awali/sttc/weightset/fwd.hh> // b
 
namespace awali { namespace sttc {
 
 
  /*------------------------.
  | complement(automaton).  |
  `------------------------*/
 
  template <typename Aut>
  Aut
  complement_here(Aut& aut)
  {
    static_assert(labelset_t_of<Aut>::is_free(),
                  "requires free labelset");
    static_assert(std::is_same<weightset_t_of<Aut>, b>::value,
                  "requires Boolean weights");
 
    // using automaton_t = Aut;
 
    require(is_deterministic(aut),
            "complement: requires a deterministic automaton");
    require(is_complete(aut),
            "complement: requires a complete automaton");
 
    // Complement.
    for (auto s: aut->states())
      if (!aut->is_final(s))
        aut->set_final(s);
      else
        aut->unset_final(s);
    return aut;
  }
 
  template <typename Aut>
  auto
  complement(const Aut& aut, bool keep_history=true)
    -> decltype(copy(aut))
  {
    auto res = copy(aut, keep_history);
    complement_here(res);
    return res;
  }
 
}}//end of ns awali::stc
 
#endif // !AWALI_ALGOS_COMPLEMENT_HH