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set::lower_bound, set::upper_bound, et set::equal_range

Illustre comment utiliser définissez : : lower_bound,définissez : : upper_bound, et des fonctions de la bibliothèque de modèles (STL) Standard de définissez : : equal_range dans Visual C++.

template<class _K, class _Pr, class _A>
   class set 
   {
      public:
      // Function 1:
      const_iterator lower_bound(const _K& _Kv) const;
      // Function 2:
      const_iterator upper_bound(const _K& _Kv) const;
      // Function 3:
      _Paircc equal_range(const _K& _Kv) const;
   }

Notes

[!REMARQUE]

Les noms de classes/paramètre dans le prototype ne correspondent pas à la version du fichier d'en-tête.certains ont été modifiés pour améliorer la lisibilité.

La fonction d' lower_bound retourne un itérateur au premier élément de la séquence contrôlée qui a une clé qui ne correspond pas à la valeur passée à la fonction de lower_bound .La fonction d' upper_bound retourne un itérateur au premier élément de la séquence contrôlée qui a une correspondance principale la valeur passée à la fonction de upper_bound .Si aucun élément n'existe, la fonction retourne fin.Dans les deux cas, la fonction set::key_comp(key, *x)*est utilisé pour déterminer si les clés correspondent.La fonction d' equal_range retourne une valeur de paires, où.First est le résultat de la fonction d' lower_bound , et .second est le résultat de la fonction d' upper_bound .

Exemple

// SetBoundRange.cpp
// compile with: /EHsc
//
//      Illustrates how to use the lower_bound function to get an
//      iterator to the earliest element in the controlled sequence
//      that has a key that does not match the value passed to the
//      function. It also illustrates how to use the upper_bound
//      function to get an iterator to the earliest element in the
//      controlled sequence that has a key that matches the value
//      passed to the function. The last thing it illustrates is
//      how to use the equal_range function to get a pair value that
//      contains the lower_bound and upper_bound results of the key.
//
// Functions:
//
//    lower_bound  Returns an iterator whose value does not match the
//                 key passed to the function, or end() if no such
//                 element exists.
//    upper_bound  Returns an iterator whose value matches the key
//                 passed to the function, or end() if no such element
//                 exists.
//    equal_range  Returns a pair of (lower_bound,upper_bound).
//////////////////////////////////////////////////////////////////////

#pragma warning(disable:4786)
#include <set>
#include <iostream>

using namespace std ;

typedef set<int> SET_INT;

int main() {
  SET_INT s1;
  SET_INT::iterator i;
  cout << "s1.insert(5)" << endl;
  s1.insert(5);
  cout << "s1.insert(10)" << endl;
  s1.insert(10);
  cout << "s1.insert(15)" << endl;
  s1.insert(15);
  cout << "s1.insert(20)" << endl;
  s1.insert(20);
  cout << "s1.insert(25)" << endl;
  s1.insert(25);

  cout << "s1 -- starting at s1.lower_bound(12)" << endl;
// prints: 15,20,25
  for (i=s1.lower_bound(12);i!=s1.end();i++)
     cout << "s1 has " << *i << " in its set." << endl;

  cout << "s1 -- starting at s1.lower_bound(15)" << endl;
// prints: 15,20,25
  for (i=s1.lower_bound(15);i!=s1.end();i++)
     cout << "s1 has " << *i << " in its set." << endl;

  cout << "s1 -- starting at s1.upper_bound(12)" << endl;
// prints: 15,20,25
  for (i=s1.upper_bound(12);i!=s1.end();i++)
     cout << "s1 has " << *i << " in its set." << endl;

  cout << "s1 -- starting at s1.upper_bound(15)" << endl;
// prints: 20,25
  for (i=s1.upper_bound(15);i!=s1.end();i++)
     cout << "s1 has " << *i << " in its set." << endl;

  cout << "s1 -- s1.equal_range(12)" << endl;
// does not print anything
  for (i=s1.equal_range(12).first;i!=s1.equal_range(12).second;i++)
     cout << "s1 has " << *i << " in its set." << endl;

  cout << "s1 -- s1.equal_range(15)" << endl;
// prints: 15
  for (i=s1.equal_range(15).first;i!=s1.equal_range(15).second;i++)
     cout << "s1 has " << *i << " in its set." << endl;
}

Sortie

s1.insert(5)
s1.insert(10)
s1.insert(15)
s1.insert(20)
s1.insert(25)
s1 -- starting at s1.lower_bound(12)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.lower_bound(15)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.upper_bound(12)
s1 has 15 in its set.
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- starting at s1.upper_bound(15)
s1 has 20 in its set.
s1 has 25 in its set.
s1 -- s1.equal_range(12)
s1 -- s1.equal_range(15)
s1 has 15 in its set.

Configuration requise

en-tête : <set>

Voir aussi

Concepts

Exemples de modèles Standard