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//        MueLu: A package for multigrid based preconditioning
//                  Copyright 2012 Sandia Corporation
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#ifndef MUELU_AGGREGATIONPHASE3ALGORITHM_KOKKOS_DECL_HPP
#define MUELU_AGGREGATIONPHASE3ALGORITHM_KOKKOS_DECL_HPP

#include "MueLu_ConfigDefs.hpp"
#ifdef HAVE_MUELU_KOKKOS_REFACTOR

#include <KokkosCompat_ClassicNodeAPI_Wrapper.hpp>

#include "MueLu_AggregationPhase3Algorithm_kokkos_fwd.hpp"

#include "MueLu_Aggregates_kokkos_fwd.hpp"
#include "MueLu_AggregationAlgorithmBase_kokkos.hpp"
#include "MueLu_FactoryBase_fwd.hpp"
#include "MueLu_LWGraph_kokkos.hpp"

namespace MueLu {
  /*!
    @class AggregationPhase3Algorithm class.
    @brief Handle leftover nodes. Try to avoid singleton nodes
    @ingroup Aggregation

    ### Idea ###
    In phase 3 we try to stick unaggregated nodes into a neighboring aggregate.
    We try to avoid singletons: we first try to build a new aggregate containing
    all neighboring non-aggregated nodes. If we cannot build a new aggregate,
    we add the non-aggregated node to the first adjacent aggregate.
    Only if there is no adjacent aggregate, we create a singleton node aggregate.

    ### Comments ###
    Only nodes with state READY are changed to AGGREGATED.

  */

  template <class LocalOrdinal = int,
            class GlobalOrdinal = LocalOrdinal,
            class Node = KokkosClassic::DefaultNode::DefaultNodeType>
  class AggregationPhase3Algorithm_kokkos :
    public MueLu::AggregationAlgorithmBase_kokkos<LocalOrdinal,GlobalOrdinal,Node> {
#undef MUELU_AGGREGATIONPHASE3ALGORITHM_KOKKOS_SHORT
#include "MueLu_UseShortNamesOrdinal.hpp"

  public:
    //! @name Constructors/Destructors.
    //@{

    //! Constructor.
    AggregationPhase3Algorithm_kokkos(const RCP<const FactoryBase>& graphFact = Teuchos::null) { }

    //! Destructor.
    virtual ~AggregationPhase3Algorithm_kokkos() { }

    //@}


    //! @name Aggregation methods.
    //@{

    /*! @brief Local aggregation. */

    void BuildAggregates(const ParameterList& params, const LWGraph_kokkos& graph, Aggregates_kokkos& aggregates, std::vector<unsigned>& aggStat, LO& numNonAggregatedNodes) const;
    //@}

    std::string description() const { return "Phase 3 (cleanup)"; }
  };

} //namespace MueLu

#define MUELU_AGGREGATIONPHASE3ALGORITHM_KOKKOS_SHORT
#endif // HAVE_MUELU_KOKKOS_REFACTOR
#endif // MUELU_AGGREGATIONPHASE3ALGORITHM_KOKKOS_DECL_HPP
