alpar@906: /* -*- C++ -*-
alpar@921:  * src/lemon/maps.h - Part of LEMON, a generic C++ optimization library
alpar@906:  *
alpar@906:  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
alpar@906:  * (Egervary Combinatorial Optimization Research Group, EGRES).
alpar@906:  *
alpar@906:  * Permission to use, modify and distribute this software is granted
alpar@906:  * provided that this copyright notice appears in all copies. For
alpar@906:  * precise terms see the accompanying LICENSE file.
alpar@906:  *
alpar@906:  * This software is provided "AS IS" with no warranty of any kind,
alpar@906:  * express or implied, and with no claim as to its suitability for any
alpar@906:  * purpose.
alpar@906:  *
alpar@906:  */
alpar@906: 
alpar@921: #ifndef LEMON_MAPS_H
alpar@921: #define LEMON_MAPS_H
klao@286: 
alpar@1041: #include<math.h>
alpar@1041: 
klao@286: ///\file
alpar@1041: ///\ingroup maps
klao@286: ///\brief Miscellaneous property maps
klao@286: ///
klao@959: ///\todo This file has the same name as the concept file in concept/,
klao@286: /// and this is not easily detectable in docs...
klao@286: 
klao@286: #include <map>
klao@286: 
alpar@921: namespace lemon {
klao@286: 
alpar@1041:   /// \addtogroup maps
alpar@1041:   /// @{
alpar@1041: 
alpar@720:   /// Base class of maps.
alpar@720: 
alpar@805:   /// Base class of maps.
alpar@805:   /// It provides the necessary <tt>typedef</tt>s required by the map concept.
alpar@720:   template<typename K, typename T>
alpar@720:   class MapBase
alpar@720:   {
alpar@720:   public:
alpar@911:     ///\e
alpar@987:     typedef K Key;
alpar@911:     ///\e
alpar@987:     typedef T Value;
alpar@720:   };
alpar@720: 
alpar@805:   /// Null map. (a.k.a. DoNothingMap)
klao@286: 
klao@286:   /// If you have to provide a map only for its type definitions,
alpar@805:   /// or if you have to provide a writable map, but
alpar@805:   /// data written to it will sent to <tt>/dev/null</tt>...
klao@286:   template<typename K, typename T>
alpar@720:   class NullMap : public MapBase<K,T>
klao@286:   {
klao@286:   public:
klao@286: 
alpar@805:     /// Gives back a default constructed element.
klao@286:     T operator[](const K&) const { return T(); }
alpar@805:     /// Absorbs the value.
klao@286:     void set(const K&, const T&) {}
klao@286:   };
klao@286: 
klao@286: 
klao@286:   /// Constant map.
klao@286: 
alpar@805:   /// This is a readable map which assigns a specified value to each key.
alpar@805:   /// In other aspects it is equivalent to the \ref NullMap.
alpar@805:   /// \todo set could be used to set the value.
klao@286:   template<typename K, typename T>
alpar@720:   class ConstMap : public MapBase<K,T>
klao@286:   {
klao@286:     T v;
klao@286:   public:
klao@286: 
alpar@805:     /// Default constructor
alpar@805: 
alpar@805:     /// The value of the map will be uninitialized. 
alpar@805:     /// (More exactly it will be default constructed.)
klao@286:     ConstMap() {}
alpar@911:     ///\e
alpar@805: 
alpar@805:     /// \param _v The initial value of the map.
alpar@911:     ///
klao@286:     ConstMap(const T &_v) : v(_v) {}
klao@286: 
klao@286:     T operator[](const K&) const { return v; }
klao@286:     void set(const K&, const T&) {}
klao@286: 
klao@286:     template<typename T1>
klao@286:     struct rebind {
klao@286:       typedef ConstMap<K,T1> other;
klao@286:     };
klao@286: 
klao@286:     template<typename T1>
klao@286:     ConstMap(const ConstMap<K,T1> &, const T &_v) : v(_v) {}
klao@286:   };
klao@286: 
marci@890:   //to document later
marci@890:   template<typename T, T v>
marci@890:   struct Const { };
marci@890:   //to document later
marci@890:   template<typename K, typename V, V v>
marci@890:   class ConstMap<K, Const<V, v> > : public MapBase<K, V>
marci@890:   {
marci@890:   public:
marci@890:     ConstMap() { }
marci@890:     V operator[](const K&) const { return v; }
marci@890:     void set(const K&, const V&) { }
marci@890:   };
klao@286: 
klao@286:   /// \c std::map wrapper
klao@286: 
klao@286:   /// This is essentially a wrapper for \c std::map. With addition that
alpar@987:   /// you can specify a default value different from \c Value() .
klao@286:   ///
klao@286:   /// \todo Provide allocator parameter...
alpar@987:   template <typename K, typename T, typename Compare = std::less<K> >
alpar@987:   class StdMap : public std::map<K,T,Compare> {
alpar@987:     typedef std::map<K,T,Compare> parent;
klao@286:     T v;
klao@286:     typedef typename parent::value_type PairType;
klao@286: 
klao@286:   public:
alpar@987:     typedef K Key;
alpar@987:     typedef T Value;
alpar@987:     typedef T& Reference;
alpar@987:     typedef const T& ConstReference;
klao@286: 
klao@286: 
klao@345:     StdMap() : v() {}
klao@286:     /// Constructor with specified default value
klao@286:     StdMap(const T& _v) : v(_v) {}
klao@286: 
klao@286:     /// \brief Constructs the map from an appropriate std::map.
klao@286:     ///
klao@286:     /// \warning Inefficient: copies the content of \c m !
klao@286:     StdMap(const parent &m) : parent(m) {}
klao@286:     /// \brief Constructs the map from an appropriate std::map, and explicitly
klao@286:     /// specifies a default value.
klao@286:     ///
klao@286:     /// \warning Inefficient: copies the content of \c m !
klao@286:     StdMap(const parent &m, const T& _v) : parent(m), v(_v) {}
klao@286:     
klao@286:     template<typename T1, typename Comp1>
marci@389:     StdMap(const StdMap<Key,T1,Comp1> &m, const T &_v) { 
marci@389:       //FIXME; 
marci@389:     }
klao@286: 
alpar@987:     Reference operator[](const Key &k) {
klao@346:       return insert(PairType(k,v)).first -> second;
klao@286:     }
alpar@987:     ConstReference operator[](const Key &k) const {
marci@389:       typename parent::iterator i = lower_bound(k);
beckerjc@391:       if (i == parent::end() || parent::key_comp()(k, (*i).first))
klao@286: 	return v;
klao@286:       return (*i).second;
klao@286:     }
klao@345:     void set(const Key &k, const T &t) {
klao@346:       parent::operator[](k) = t;
klao@345:     }
klao@286: 
klao@286:     /// Changes the default value of the map.
klao@286:     /// \return Returns the previous default value.
klao@286:     ///
alpar@805:     /// \warning The value of some keys (which has already been queried, but
klao@286:     /// the value has been unchanged from the default) may change!
klao@286:     T setDefault(const T &_v) { T old=v; v=_v; return old; }
klao@286: 
klao@286:     template<typename T1>
klao@286:     struct rebind {
klao@286:       typedef StdMap<Key,T1,Compare> other;
klao@286:     };
klao@286:   };
alpar@1041: 
alpar@1041: 
alpar@1041:   ///Sum of two maps
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the sum of the two
alpar@1041:   ///given maps. Its \c Key and \c Value will be inherited from \c M1.
alpar@1041:   ///The \c Key and \c Value of M2 must be convertible to those of \c M1.
alpar@1041: 
alpar@1041:   template<class M1,class M2> 
alpar@1041:   class AddMap
alpar@1041:   {
alpar@1041:     const M1 &m1;
alpar@1041:     const M2 &m2;
alpar@1041:   public:
alpar@1041:     typedef typename M1::Key Key;
alpar@1041:     typedef typename M1::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     AddMap(const M1 &_m1,const M2 &_m2) : m1(_m1), m2(_m2) {};
alpar@1041:     Value operator[](Key k) {return m1[k]+m2[k];}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns an \ref AddMap class
alpar@1041: 
alpar@1041:   ///This function just returns an \ref AddMap class.
alpar@1041:   ///\todo How to call these type of functions?
alpar@1041:   ///
alpar@1041:   ///\relates AddMap
alpar@1041:   ///\todo Wrong scope in Doxygen when \c \\relates is used
alpar@1041:   template<class M1,class M2> 
alpar@1041:   inline AddMap<M1,M2> addMap(const M1 &m1,const M2 &m2) 
alpar@1041:   {
alpar@1041:     return AddMap<M1,M2>(m1,m2);
alpar@1041:   }
alpar@1041: 
alpar@1041:   ///Difference of two maps
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the difference
alpar@1041:   ///of the values returned by the two
alpar@1041:   ///given maps. Its \c Key and \c Value will be inherited from \c M1.
alpar@1041:   ///The \c Key and \c Value of \c M2 must be convertible to those of \c M1.
alpar@1041: 
alpar@1041:   template<class M1,class M2> 
alpar@1041:   class SubMap
alpar@1041:   {
alpar@1041:     const M1 &m1;
alpar@1041:     const M2 &m2;
alpar@1041:   public:
alpar@1041:     typedef typename M1::Key Key;
alpar@1041:     typedef typename M1::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     SubMap(const M1 &_m1,const M2 &_m2) : m1(_m1), m2(_m2) {};
alpar@1041:     Value operator[](Key k) {return m1[k]-m2[k];}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns a \ref SubMap class
alpar@1041: 
alpar@1041:   ///This function just returns a \ref SubMap class.
alpar@1041:   ///
alpar@1041:   ///\relates SubMap
alpar@1041:   template<class M1,class M2> 
alpar@1041:   inline SubMap<M1,M2> subMap(const M1 &m1,const M2 &m2) 
alpar@1041:   {
alpar@1041:     return SubMap<M1,M2>(m1,m2);
alpar@1041:   }
alpar@1041: 
alpar@1041:   ///Product of two maps
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the product of the
alpar@1041:   ///values returned by the two
alpar@1041:   ///given
alpar@1041:   ///maps. Its \c Key and \c Value will be inherited from \c M1.
alpar@1041:   ///The \c Key and \c Value of \c M2 must be convertible to those of \c M1.
alpar@1041: 
alpar@1041:   template<class M1,class M2> 
alpar@1041:   class MulMap
alpar@1041:   {
alpar@1041:     const M1 &m1;
alpar@1041:     const M2 &m2;
alpar@1041:   public:
alpar@1041:     typedef typename M1::Key Key;
alpar@1041:     typedef typename M1::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     MulMap(const M1 &_m1,const M2 &_m2) : m1(_m1), m2(_m2) {};
alpar@1041:     Value operator[](Key k) {return m1[k]*m2[k];}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns a \ref MulMap class
alpar@1041: 
alpar@1041:   ///This function just returns a \ref MulMap class.
alpar@1041:   ///\relates MulMap
alpar@1041:   template<class M1,class M2> 
alpar@1041:   inline MulMap<M1,M2> mulMap(const M1 &m1,const M2 &m2) 
alpar@1041:   {
alpar@1041:     return MulMap<M1,M2>(m1,m2);
alpar@1041:   }
alpar@1041:  
alpar@1041:   ///Quotient of two maps
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the quotient of the
alpar@1041:   ///values returned by the two
alpar@1041:   ///given maps. Its \c Key and \c Value will be inherited from \c M1.
alpar@1041:   ///The \c Key and \c Value of \c M2 must be convertible to those of \c M1.
alpar@1041: 
alpar@1041:   template<class M1,class M2> 
alpar@1041:   class DivMap
alpar@1041:   {
alpar@1041:     const M1 &m1;
alpar@1041:     const M2 &m2;
alpar@1041:   public:
alpar@1041:     typedef typename M1::Key Key;
alpar@1041:     typedef typename M1::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     DivMap(const M1 &_m1,const M2 &_m2) : m1(_m1), m2(_m2) {};
alpar@1041:     Value operator[](Key k) {return m1[k]/m2[k];}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns a \ref DivMap class
alpar@1041: 
alpar@1041:   ///This function just returns a \ref DivMap class.
alpar@1041:   ///\relates DivMap
alpar@1041:   template<class M1,class M2> 
alpar@1041:   inline DivMap<M1,M2> divMap(const M1 &m1,const M2 &m2) 
alpar@1041:   {
alpar@1041:     return DivMap<M1,M2>(m1,m2);
alpar@1041:   }
alpar@1041:   
alpar@1041:   ///Composition of two maps
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the composition of
alpar@1041:   ///two
alpar@1041:   ///given maps. That is to say, if \c m1 is of type \c M1 and \c m2 is
alpar@1041:   ///of \c M2,
alpar@1041:   ///then for
alpar@1041:   ///\code
alpar@1041:   ///  ComposeMap<M1,M2> cm(m1,m2);
alpar@1041:   ///\endcode
alpar@1041:   ///<tt>cm[x]</tt> will be equal to <tt>m1[m2[x]]</tt>
alpar@1041:   ///
alpar@1041:   ///Its \c Key is inherited from \c M2 and its \c Value is from
alpar@1041:   ///\c M1.
alpar@1041:   ///The \c M2::Value must be convertible to \c M1::Key.
alpar@1041:   ///\todo Check the requirements.
alpar@1041: 
alpar@1041:   template<class M1,class M2> 
alpar@1041:   class ComposeMap
alpar@1041:   {
alpar@1041:     const M1 &m1;
alpar@1041:     const M2 &m2;
alpar@1041:   public:
alpar@1041:     typedef typename M2::Key Key;
alpar@1041:     typedef typename M1::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     ComposeMap(const M1 &_m1,const M2 &_m2) : m1(_m1), m2(_m2) {};
alpar@1041:     Value operator[](Key k) {return m1[m2[k]];}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns a \ref ComposeMap class
alpar@1041: 
alpar@1041:   ///This function just returns a \ref ComposeMap class.
alpar@1041:   ///\relates ComposeMap
alpar@1041:   template<class M1,class M2> 
alpar@1041:   inline ComposeMap<M1,M2> composeMap(const M1 &m1,const M2 &m2) 
alpar@1041:   {
alpar@1041:     return ComposeMap<M1,M2>(m1,m2);
alpar@1041:   }
alpar@1041: 
alpar@1041:   ///Negative value of a map
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the negative
alpar@1041:   ///value of the
alpar@1041:   ///value returned by the
alpar@1041:   ///given map. Its \c Key and \c Value will be inherited from \c M.
alpar@1041:   ///The unary \c - operator must be defined for \c Value, of course.
alpar@1041: 
alpar@1041:   template<class M> 
alpar@1041:   class NegMap
alpar@1041:   {
alpar@1041:     const M &m;
alpar@1041:   public:
alpar@1041:     typedef typename M::Key Key;
alpar@1041:     typedef typename M::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     NegMap(const M &_m) : m(_m) {};
alpar@1041:     Value operator[](Key k) {return -m[k];}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns a \ref NegMap class
alpar@1041: 
alpar@1041:   ///This function just returns a \ref NegMap class.
alpar@1041:   ///\relates NegMap
alpar@1041:   template<class M> 
alpar@1041:   inline NegMap<M> negMap(const M &m) 
alpar@1041:   {
alpar@1041:     return NegMap<M>(m);
alpar@1041:   }
alpar@1041: 
alpar@1041: 
alpar@1041:   //\todo We need a unified way to handle the situation below!
alpar@1041:   struct _UnConvertible {};
alpar@1041:   template<class A> inline A t_abs(A a) {return _UnConvertible();}
alpar@1041: 
alpar@1041:   template<> inline int t_abs<>(int n) {return abs(n);}
alpar@1041:   template<> inline long int t_abs<>(long int n) {return labs(n);}
alpar@1041:   //\bug llabs() is overloaded
alpar@1041:   template<> inline long long int t_abs<>(long long int n) {return ::llabs(n);}
alpar@1041: 
alpar@1041:   template<> inline float t_abs<>(float n) {return fabsf(n);}
alpar@1041:   template<> inline double t_abs<>(double n) {return fabs(n);}
alpar@1041:   template<> inline long double t_abs<>(long double n) {return fabsl(n);}
alpar@1041: 
alpar@1041:   ///Absolute value of a map
alpar@1041: 
alpar@1041:   ///This \ref concept::ReadMap "read only map" returns the absolute value
alpar@1041:   ///of the
alpar@1041:   ///value returned by the
alpar@1041:   ///given map. Its \c Key and \c Value will be inherited from \c M.
alpar@1041:   ///The function <tt>Value abs(Value)<tt> must be defined, of course.
alpar@1041: 
alpar@1041:   template<class M> 
alpar@1041:   class AbsMap
alpar@1041:   {
alpar@1041:     const M &m;
alpar@1041:   public:
alpar@1041:     typedef typename M::Key Key;
alpar@1041:     typedef typename M::Value Value;
alpar@1041: 
alpar@1041:     ///Constructor
alpar@1041: 
alpar@1041:     ///\e
alpar@1041:     ///
alpar@1041:     AbsMap(const M &_m) : m(_m) {};
alpar@1041:     Value operator[](Key k) {return t_abs(m[k]);}
alpar@1041:   };
alpar@1041:   
alpar@1041:   ///Returns a \ref AbsMap class
alpar@1041: 
alpar@1041:   ///This function just returns a \ref AbsMap class.
alpar@1041:   ///\relates AbsMap
alpar@1041:   template<class M> 
alpar@1041:   inline AbsMap<M> absMap(const M &m) 
alpar@1041:   {
alpar@1041:     return AbsMap<M>(m);
alpar@1041:   }
alpar@1041: 
alpar@1041:   /// @}
klao@286:   
klao@286: }
alpar@1041: 
alpar@1041: 
alpar@921: #endif // LEMON_MAPS_H