DLPermutation.H

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License
    This file is part of OpenFOAM.
 
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    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.
 
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    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
Class
    Foam::DLPermutation
 
Description
    A permutation stored in the same manner as a doubly-linked list in order to
    facilitate reordering in constant time
 
SourceFiles
    DLPermutationI.H
 
\*---------------------------------------------------------------------------*/
 
#ifndef DLPermutation_H
#define DLPermutation_H
 
#include "randomGenerator.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
 
/*---------------------------------------------------------------------------*\
                        Class DLPermutation Declaration
\*---------------------------------------------------------------------------*/
 
template<class LabelList>
class DLPermutation
{
    // Private Data
 
        //- The first index
        label head_;
 
        //- For every index, the next index
        LabelList next_;
 
        //- The last index
        label tail_;
 
        //- For every index, the previous index
        LabelList previous_;
 
 
public:
 
    // Public Classes
 
        //- A bi-directional constant iterator
        class const_iterator
        {
            // Private Data
 
                //- Reference to the permutation
                const DLPermutation& p_;
 
                //- The current index
                label i_;
 
 
        public:
 
            // Constructors
 
                //- Construct at an index within a permutation
                inline const_iterator(const DLPermutation&, const label);
 
                //- Use the default copy constructor
                inline const_iterator(const const_iterator&) = default;
 
 
            // Member Operators
 
                //- Dereference
                inline label operator*() const;
 
                //- Assignment
                inline const_iterator& operator=(const const_iterator& iter);
 
                //- Increment
                inline const_iterator& operator++();
 
                //- Increment
                inline const_iterator operator++(int);
 
                //- Decrement
                inline const_iterator& operator--();
 
                //- Decrement
                inline const_iterator operator--(int);
 
                //- Equality comparison
                inline bool operator==(const const_iterator& iter) const;
 
                //- Inequality comparison
                inline bool operator!=(const const_iterator& iter) const;
 
 
            // Member Functions
 
                //- Return the next iterator without incrementing
                inline const_iterator next() const;
 
                //- Return the previous iterator without incrementing
                inline const_iterator previous() const;
        };
 
 
    // Constructors
 
        //- Construct for a given permutation
        inline DLPermutation(const List<label>& permutation);
 
        //- Construct a random permutation
        inline DLPermutation(const label n, randomGenerator& rndGen);
 
 
    // Member Functions
 
        //- Return the permutation
        inline List<label> permutation(const bool reverse);
 
        //- Return the starting forward iterator
        inline const_iterator begin() const;
 
        //- Return the ending forward iterator
        inline const_iterator end() const;
 
        //- Return the starting forward iterator
        inline const_iterator cbegin() const;
 
        //- Return the ending forward iterator
        inline const_iterator cend() const;
 
        //- Return the starting reverse iterator
        inline const_iterator rbegin() const;
 
        //- Return the ending reverse iterator
        inline const_iterator rend() const;
 
        //- Return the starting reverse iterator
        inline const_iterator crbegin() const;
 
        //- Return the ending reverse iterator
        inline const_iterator crend() const;
 
        //- Add a new index to the end of the permutation
        void append();
 
        //- Add a new index to the start of the permutation
        void prepend();
 
        //- Raise a given index to the start of the permutation
        void raise(const label i);
 
        //- Sink a given index to the end of the permutation
        void sink(const label i);
 
        // !!! More operations are possible; e.g., swap two elements or rotate
        // a sub-section. Implement as necessary.
};
 
 
//- Define the type of a permutation based on a list
typedef DLPermutation<List<label>> dLPermutation;
 
 
//- Define the type of a permutation based on a dynamic list
typedef DLPermutation<DynamicList<label>> dynamicDLPermutation;
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace Foam
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#define forAllConstIterReverse(Container,container,iter)                       \
    for                                                                        \
    (                                                                          \
        Container::const_iterator iter = (container).rbegin();                 \
        iter != (container).rend();                                            \
        -- iter                                                                \
    )
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#include "DLPermutationI.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
#endif
 
// ************************************************************************* //