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Jt-Polys-Cours-11.Pdf Notes de cours Standard Template Library ' $ ' $ Ecole Nationale d’Ing´enieurs de Brest Table des mati`eres L’approche STL ................................... 3 Les it´erateurs .................................... 15 Les classes de fonctions .......................... 42 Programmation par objets Les conteneurs ................................... 66 Le langage C++ Les adaptateurs ................................. 134 — Standard Template Library — Les algorithmes g´en´eriques ...................... 145 Index ........................................... 316 J. Tisseau R´ef´erences ...................................... 342 – 1996/1997 – enib c jt ........ 1/344 enib c jt ........ 2/344 & % & % Standard Template Library L’approche STL ' $ ' $ L’approche STL Biblioth`eque de composants C++ g´en´eriques L’approche STL Fonctions : algorithmes g´en´eriques 1. Une biblioth`eque de composants C++ g´en´eriques sort, binary search, reverse, for each, accumulate,... 2. Du particulier au g´en´erique Conteneurs : collections homog`enes d’objets 3. Des indices aux it´erateurs, via les pointeurs vector, list, set, map, multimap,... 4. De la g´en´ericit´edes donn´ees `ala g´en´ericit´edes structures It´erateurs : sorte de pointeurs pour inspecter un conteneur input iterator, random access iterator, ostream iterator,... Objets fonction : encapsulation de fonctions dans des objets plus, times, less equal, logical or,... Adaptateurs : modificateurs d’interfaces de composants stack, queue, priority queue,... enib c jt ........ 3/344 enib c jt ........ 4/344 & % & % L’approche STL L’approche STL ' $ ' $ Du particulier . au g´en´erique int template <class T> max(int x, int y) { return x < y? y : x; } const T& max(const T& x, const T& y) { return x < y? y : x; } int template <class T, class Compare> max(int x, int y, int (*compare)(int,int)) { const T& return compare(x,y)? y : x; max(const T& x, const T& y, Compare compare) { } return compare(x, y)? y : x; } enib c jt ........ 5/344 enib c jt ........ 6/344 & % & % L’approche STL L’approche STL ' $ ' $ Des indices . ... via les pointeurs ... int int* max element(const int* array, int n) { max element(int* first, int* last) { int result = array[0]; if(first == last) return first; for(int i = 1; i < n; i++) int* result = first; if(result < array[i]) result = array[i]; while(++first!= last) return result; if(*result < *first) result = first; } return result; } enib c jt ........ 7/344 enib c jt ........ 8/344 & % & % L’approche STL L’approche STL ' $ ' $ . aux it´erateurs g´en´eriques max element (2) STL algo.h template <class InputIterator> template <class InputIterator, class Compare> InputIterator InputIterator max element(InputIterator first, InputIterator last) { max element(InputIterator first, InputIterator last, if(first == last) return first; Compare compare) { InputIterator result = first; if (first == last) return first; while(++first!= last) InputIterator result = first; if(*result < *first) result = first; while(++first!= last) return result; if(compare(*result,*first)) result = first; } return result; } enib c jt ........ 9/344 enib c jt ....... 10/344 & % & % L’approche STL L’approche STL ' $ ' $ Exemple d’utilisation : max element (2) De la g´en´ericit´edes donn´ees . bool str compare(const char* a, const char* b) { // Sequences return : :strcmp(a, b) < 0? 1 : 0; template <class T> class vector; } template <class T> class deque; template <class T> class list; char* names[] = { "Dany", "Alexis", "Serge", "Vincent" } ; // Associative containers cout << *max element(names, names + 4, str compare) << endl; template <class T1, class T2> class pair; template <class Key, class Compare> class set; template <class Key, class Compare> class multiset; template <class Key, class T, class Compare> class map; template <class Key, class T, class Compare> class multimap ; enib c jt ....... 11/344 enib c jt ....... 12/344 & % & % L’approche STL L’approche STL ' $ ' $ . `ala g´en´ericit´edes structures Exemple d’utilisation : stack // Containers adaptors stack< deque<int> > s1; template <class Container> class stack; stack< vector<int> > s2; template <class Container> class queue; template <class Container> class priority queue ; s1.push(42); s1.push(101); s1.push(69); copy(s1.begin(), s1.end(), s2.begin()); // Instantiations stack< vector<double> > s; while( !s2.empty()) { queue< deque<const char*> > q; cout << s2.top() << endl; priority queue< list<int> > p; s2.pop() ; } enib c jt ....... 13/344 enib c jt ....... 14/344 & % & % Standard Template Library It´erateurs ' $ ' $ Les it´erateurs Des pointeurs sp´ecialis´es (p2 < p) -= m p += n (p1 > p) • •Z • Z Z Les it´erateurs -- ++Z ? ? = ? Z~ ? ? 1. Des pointeurs sp´ecialis´es ........................ ....... 16 *p 2. output iterator ........................................ 18 p[n] Pointer 3. input iterator<T,Distance> ............................. 21 t1 = *p; *p = t2; 4. forward iterator<T,Distance> ........................... 25 p bidirectional iterator<T,Distance> •Z 5. ..................... 29 Z Z ++Z 6. random access iterator<T,Distance> ..................... 34 ? Z~ 7. It´erateurs d´eriv´es ............................. ......... 36 *p InputIterator 8. Exemples d’utilisation ............................ ...... 38 t1 = *p; enib c jt ....... 15/344 enib c jt ....... 16/344 & % & % It´erateurs It´erateurs ' $ ' $ It´erateurs de base output iterator p •Z Z Z ++Z struct output iterator {} ; ? Z~ *p OutputIterator template <class T, class Distance> struct input iterator {} ; *p = t2; template <class T, class Distance> class OutputIterator : public output iterator { struct forward iterator {} ; public : T& operator*(void); template <class T, class Distance> OutputIterator& operator++(void); struct bidirectional iterator {} ; OutputIterator operator++(int); } ; template <class T, class Distance> struct random access iterator {} ; enib c jt ....... 17/344 enib c jt ....... 18/344 & % & % It´erateurs It´erateurs ' $ ' $ Exemple de d´efinition : output iterator (1) Exemple de d´efinition : output iterator (2) template <class T> OstreamIterator<T>& operator=(const T& value) { class OstreamIterator : public output iterator { * stream << value; protected : if( string) * stream << string ; ostream* stream ; return *this; char* string ; } public : OstreamIterator<T>& operator*(void) { return *this; } OstreamIterator(ostream& s) : stream(&s), string(0) {} OstreamIterator<T>& operator++(void) { return *this; } OstreamIterator(ostream& s, char* c) OstreamIterator<T>& operator++(int) { return *this; } : stream(&s), string(c) {} } ; // end class OstreamIterator<T> `asuivre ... ... fin enib c jt ....... 19/344 enib c jt ....... 20/344 & % & % It´erateurs It´erateurs ' $ ' $ input iterator<T,Distance> Exemple de d´efinition : input iterator<T,Distance> (1) p •Z Z Z ++Z template <class T> ? Z~ class IstreamIterator : public input iterator<T,ptrdiff t> { *p InputIterator protected : t1 = *p; istream* stream ; T value; bool endMarker ; template <class T, class Distance> class InputIterator : public input iterator<T,Distance> { void read() { public : endMarker = (* stream)? true : false; const T& operator*(void) const; if( endMarker) * stream >> value; InputIterator<T,Distance>& operator++(void) ; endMarker = (* stream)? true : false; InputIterator<T,Distance> operator++(int) ; } } ; `asuivre ... enib c jt ....... 21/344 enib c jt ....... 22/344 & % & % It´erateurs It´erateurs ' $ ' $ Exemple de d´efinition : input iterator<T,Distance> (2) Exemple de d´efinition : input iterator<T,Distance> (3) public : friend bool operator==(const IstreamIterator<T>& x, IstreamIterator(void) const IstreamIterator<T>& y) { : stream(&cin), endMarker(false) {} return x. stream == y. stream && IstreamIterator(istream& s) : stream(&s) { read() ; } x. endMarker == y. endMarker const T& operator*(void) const { return value ; } || IstreamIterator<T>& operator++(void) { x. endMarker == false && read(); return *this; y. endMarker == false; } } IstreamIterator<T> operator++(int) { } ; // end class IstreamIterator<T> IstreamIterator<T> tmp = *this; read(); return tmp; ... fin } `asuivre ... enib c jt ....... 23/344 enib c jt ....... 24/344 & % & % It´erateurs It´erateurs ' $ ' $ forward iterator<T,Distance> Exemple de d´efinition : forward iterator (1) p •Z Z Z ++Z template <class T> ? Z~ struct list node { void* next; T data; } ; *p ForwardIterator t1 = *p; *p = t2; template <class T> class list iterator : public forward iterator<T,ptrdiff t> { protected : template <class T, class Distance> class ForwardIterator : public forward iterator<T,Distance> { list node<T>* node; public : list iterator(list node<T>* x) : node(x) {} T& operator*(void); const T& operator*(void) const; `asuivre ... ForwardIterator& operator++(void) ; ForwardIterator operator++(int); } ; enib c jt ....... 25/344 enib c jt ....... 26/344 & % & % It´erateurs It´erateurs ' $ ' $ Exemple de d´efinition : forward iterator (2) Exemple de d´efinition : forward iterator (3) public : list iterator& operator++(void) { list iterator(void) {} node = (list node*)((* node).next); return *this; } bool operator==(const list iterator& x) const { return node == x. node; list iterator operator++(int) { } list iterator tmp = *this; ++*this; return tmp; } T& operator*(void) const { return (* node).data ; } } ; ... fin `asuivre ... enib c jt ....... 27/344 enib c jt ....... 28/344 & % & % It´erateurs It´erateurs ' $ ' $ bidirectional iterator<T,Distance> Exemple de d´efinition : bidirectional iterator (1) p •Z Z Z -- ++Z = ? Z~ template <class T> struct
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