Program Listing for File SplayTree.h

↰ Return to documentation for file (ADS/tree/SplayTree.h)

/*--------------------------------------------------------------------------*/
/*---------------------------- File SplayTree.h ----------------------------*/
/*--------------------------------------------------------------------------*/
/*--------------------------------------------------------------------------*/
/*----------------------------- DEFINITIONS --------------------------------*/
/*--------------------------------------------------------------------------*/

#ifndef __ADS_SplayTree
 #define __ADS_SplayTree
                      /* self-identification: #endif constant */

/*--------------------------------------------------------------------------*/
/*------------------------------ INCLUDES ----------------------------------*/
/*--------------------------------------------------------------------------*/

#include "ADS/Contract.h"
#include "ADS/Iterators.h"

#include <concepts>
#include <cstddef>
#include <memory>
#include <optional>
#include <utility>
#include <vector>

/*--------------------------------------------------------------------------*/
/*--------------------------- NAMESPACE ------------------------------------*/
/*--------------------------------------------------------------------------*/

namespace ADS {

/*--------------------------------------------------------------------------*/
/*--------------------------- CLASS SplayTree ------------------------------*/
/*--------------------------------------------------------------------------*/

template< std::totally_ordered K , class V >
class SplayTree {

/*--------------------------------------------------------------------------*/
 public:

 using Key = K;
 using Value = V;

 SplayTree( void ) = default;
 SplayTree( const SplayTree & ) = delete;
 SplayTree & operator=( const SplayTree & ) = delete;

 SplayTree( SplayTree && other ) noexcept;
 ~SplayTree();

 [[nodiscard]] std::optional< V > lookup( const K & k );

 void insert( const K & k , const V & v );

 void remove( const K & k );

 [[nodiscard]] std::size_t size( void ) const;

 [[nodiscard]] std::optional< K > root( void ) const;

 template< class F >
 void forEach( F && f ) const;

/*--------------------------------------------------------------------------*/
 private:

 struct Node {
  K key;
  V value;
  Node * left = nullptr , * right = nullptr;
  };

 public:

/*------------------------- THE STANDARD INTERFACE -------------------------*/

 // a constant view of the pairs ( key , value ) by increasing key,
 // bidirectional, along the path from the root; a lookup splays the tree
 // and invalidates it

 struct Shape {
  static auto root( const auto & o ) { return( o.f_root ); }
  static auto left( const auto * n ) { return( n->left ); }
  static auto right( const auto * n ) { return( n->right ); }
  static auto read( const auto * n ) {
   return( std::pair< const K & , const V & >( n->key , n->value ) );
   }
  };

 using value_type = std::pair< const K & , const V & >;
 using size_type = std::size_t;
 using difference_type = std::ptrdiff_t;
 using reference = value_type;
 using const_reference = value_type;
 using const_iterator = PathIterator< SplayTree , Shape >;
 using iterator = const_iterator;

 [[nodiscard]] const_iterator begin( void ) const {
  return( const_iterator( this , true ) );
  }
 [[nodiscard]] const_iterator end( void ) const {
  return( const_iterator( this , false ) );
  }
 [[nodiscard]] const_iterator cbegin( void ) const { return( begin() ); }
 [[nodiscard]] const_iterator cend( void ) const { return( end() ); }

 private:

 static Node * splay( Node * t , const K & k );

 static void destroy( Node * t );

 template< class F >
 static void visit( const Node * t , F & f );

 static bool ordered( const Node * t , const K * lo , const K * hi );

 Node * f_root = nullptr;
 std::size_t f_size = 0;

 };  // end( class SplayTree )

/*--------------------------------------------------------------------------*/

}  // end( namespace ADS )

/*--------------------------------------------------------------------------*/
/*-------------------------- IMPLEMENTATION --------------------------------*/
/*--------------------------------------------------------------------------*/

#include "ADS/tree/impl/SplayTree.tpp"

/*--------------------------------------------------------------------------*/

#endif  /* SplayTree.h included */

/*--------------------------------------------------------------------------*/
/*-------------------------- End File SplayTree.h --------------------------*/
/*--------------------------------------------------------------------------*/