Quelle kbe.hpp Sprache: C

//
// libsemigroups - C++ library for semigroups and monoids
// Copyright (C) 2019 James D. Mitchell
//
// 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/>.
//

// This file contains the declaration of the class KBE, which can be used as
// the element_type for a FroidurePin instance. This class just wraps a
// reduced word of a KnuthBendix instance.

// For technical reasons this is implemented in src/kbe-impl.hpp

#ifndef LIBSEMIGROUPS_KBE_HPP_
#define LIBSEMIGROUPS_KBE_HPP_

#include <cstddef>  // for size_t
#include <string>   // for string
#include <utility>  // for hash

#include "adapters.hpp"      // for One
#include "froidure-pin.hpp"  // for FroidurePin
#include "knuth-bendix.hpp"  // for fpsemigroup::KnuthBendix
#include "types.hpp"         // for word_type, letter_type

namespace libsemigroups {
  namespace detail {
    // This class is used to wrap libsemigroups::internal_string_type into an
    // object that can be used as generators for a FroidurePin object.
    class KBE final {
      using KnuthBendix          = fpsemigroup::KnuthBendix;
      using internal_string_type = std::string;

      KBE(internal_string_type const&);
      KBE(internal_string_type&&);

     public:
      KBE() = default;

      KBE(KBE const&) = default;
      KBE(KBE&&)      = default;

      KBE& operator=(KBE const&) = default;
      KBE& operator=(KBE&&)      = default;

      ~KBE() = default;

      // Construct from internal string
      KBE(KnuthBendix&, internal_string_type const&);
      KBE(KnuthBendix&, internal_string_type&&);

      // Construct from external types
      KBE(KnuthBendix&, letter_type const&);
      KBE(KnuthBendix&, word_type const&);

      bool operator==(KBE const&) const;
      bool operator<(KBE const&) const;
      void swap(KBE&);

      internal_string_type const& string() const noexcept;
      std::string                 string(KnuthBendix const& kb) const;
      word_type                   word(KnuthBendix const& kb) const;

      friend std::ostringstream& operator<<(std::ostringstream& os,
                                            KBE const&          kbe) {
        os << kbe.string();
        return os;
      }

     private:
      internal_string_type _kb_word;
    };
    // The following are not really required but are here as a reminder that
    // KBE are used in BruidhinnTraits which depends on the values in the
    // static_asserts below.
    static_assert(!std::is_trivial<KBE>::value, "KBE is trivial!!!");
    static_assert(std::integral_constant<bool, (sizeof(KBE) <= 32)>::value,
                  "KBE's sizeof exceeds 32!!");

  }  // namespace detail

  ////////////////////////////////////////////////////////////////////////
  // Adapters for KBE class
  ////////////////////////////////////////////////////////////////////////

  template <>
  struct Complexity<detail::KBE> {
    constexpr size_t operator()(detail::KBE const&) const noexcept {
      return LIMIT_MAX;
    }
  };

  template <>
  struct Degree<detail::KBE> {
    constexpr size_t operator()(detail::KBE const&) const noexcept {
      return 0;
    }
  };

  template <>
  struct IncreaseDegree<detail::KBE> {
    void operator()(detail::KBE const&, size_t) const noexcept {}
  };

  template <>
  struct One<detail::KBE> {
    detail::KBE operator()(detail::KBE const&) const noexcept {
      return detail::KBE();
    }

    detail::KBE operator()(size_t = 0) const noexcept {
      return detail::KBE();
    }
  };

  template <>
  struct Product<detail::KBE> {
    void operator()(detail::KBE&              xy,
                    detail::KBE const&        x,
                    detail::KBE const&        y,
                    fpsemigroup::KnuthBendix* kb,
                    size_t) {
      std::string w(x.string());  // internal_string_type
      w += y.string();
      xy = detail::KBE(*kb, w);
    }
  };

  template <>
  word_type
  FroidurePin<detail::KBE,
              FroidurePinTraits<detail::KBE, fpsemigroup::KnuthBendix>>::
      factorisation(detail::KBE const& x);

  template <>
  tril FroidurePin<detail::KBE,
                   FroidurePinTraits<detail::KBE, fpsemigroup::KnuthBendix>>::
      is_finite() const;
}  // namespace libsemigroups

////////////////////////////////////////////////////////////////////////
// Specializations of std::hash and std::equal_to
////////////////////////////////////////////////////////////////////////

namespace std {
  template <>
  struct hash<libsemigroups::detail::KBE> {
    size_t operator()(libsemigroups::detail::KBE const& x) const {
      return hash<string>()(x.string());
    }
  };

  template <>
  struct equal_to<libsemigroups::detail::KBE> {
    bool operator()(libsemigroups::detail::KBE const& x,
                    libsemigroups::detail::KBE const& y) const {
      return x == y;
    }
  };
}  // namespace std
#endif  // LIBSEMIGROUPS_KBE_HPP_

quality92%

¤ Dauer der Verarbeitung: 0.17 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.