std::find, std::find_if, std::find_if_not
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| Dclar dans l'en-tte <algorithm>
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template< class InputIt, class T > InputIt find( InputIt first, InputIt last, const T& value ); |
(1) | |
template< class InputIt, class UnaryPredicate > InputIt find_if( InputIt first, InputIt last, UnaryPredicate p ); |
(2) | |
template< class InputIt, class UnaryPredicate > InputIt find_if_not( InputIt first, InputIt last, UnaryPredicate q ); |
(3) | (depuis C++11) |
Ces fonctions trouver le premier lment de la
[first, last) gamme qui rpond des critres spcifiques:Original:
These functions find the first element in the range
[first, last) that satisfies specific criteria:The text has been machine-translated via Google Translate.
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1.
find recherches pour un lment gal valueOriginal:
1.
find searches for an element equal to valueThe text has been machine-translated via Google Translate.
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2.
find_if recherches pour un lment pour lequel prdicat retourne p trueOriginal:
2.
find_if searches for an element for which predicate p returns trueThe text has been machine-translated via Google Translate.
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You can help to correct and verify the translation. Click here for instructions.
3.
find_if_not recherches pour lment pour lequel prdicat retourne q falseOriginal:
3.
find_if_not searches for element for which predicate q returns falseThe text has been machine-translated via Google Translate.
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Paramtres
| first, last | - | l'ventail des lments examiner
Original: the range of elements to examine The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
| value | - | valeur comparer les lments d'
Original: value to compare the elements to The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
| p | - | prdicat unaire qui retourne true pour l'lment requis . Original: for the required element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. L'expression |
| q | - | prdicat unaire qui retourne false pour l'lment requis . Original: for the required element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. L'expression |
| Type requirements | ||
-InputIt must meet the requirements of InputIterator.
| ||
Retourne la valeur
Itrateur sur le premier lment satisfaisant la condition ou
last si aucun lment correspondant n'est trouv .Original:
Iterator to the first element satisfying the condition or
last if no such element is found.The text has been machine-translated via Google Translate.
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Complexit
Tout au plus
last - first applications du prdicatOriginal:
At most
last - first applications of the predicateThe text has been machine-translated via Google Translate.
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Mise en uvre possible
| First version |
|---|
template<class InputIt, class T>
InputIt find(InputIt first, InputIt last, const T& value)
{
for (; first != last; ++first) {
if (*first == value) {
return first;
}
}
return last;
}
|
| Second version |
template<class InputIt, class UnaryPredicate>
InputIt find_if(InputIt first, InputIt last, UnaryPredicate p)
{
for (; first != last; ++first) {
if (p(*first)) {
return first;
}
}
return last;
}
|
| Third version |
template<class InputIt, class UnaryPredicate>
InputIt find_if_not(InputIt first, InputIt last, UnaryPredicate q)
{
for (; first != last; ++first) {
if (!q(*first)) {
return first;
}
}
return last;
}
|
Si vous n'avez pas de C++11, un quivalent de std::find_if_not est d'utiliser std::find_if avec le prdicat ni .
Original:
If you do not have C++11, an equivalent to std::find_if_not is to use std::find_if with the negated predicate.
The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
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template<class InputIt, class UnaryPredicate>
InputIt find_if_not(InputIt first, InputIt last, UnaryPredicate q)
{
return std::find_if(first, last, std::not1(q));
}
|
Exemple
L'exemple suivant recherche un entier dans un vecteur d'entiers .
Original:
The following example finds an integer in a vector of integers.
The text has been machine-translated via Google Translate.
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#include <iostream>
#include <algorithm>
#include <vector>
int main()
{
int n1 = 3;
int n2 = 5;
std::vector<int> v{0, 1, 2, 3, 4};
auto result1 = std::find(v.begin(), v.end(), n1);
auto result2 = std::find(v.begin(), v.end(), n2);
if (result1 != v.end()) {
std::cout << "v contains: " << n1 << '\n';
} else {
std::cout << "v does not contain: " << n1 << '\n';
}
if (result2 != v.end()) {
std::cout << "v contains: " << n2 << '\n';
} else {
std::cout << "v does not contain: " << n2 << '\n';
}
}
Rsultat :
v contains: 3
v does not contain: 5
Voir aussi
trouve deux identiques (ou une autre relation) des lments adjacents les uns aux autres Original: finds two identical (or some other relationship) items adjacent to each other The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (fonction gnrique) | |
trouve la dernire squence d'lments dans une certaine plage Original: finds the last sequence of elements in a certain range The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (fonction gnrique) | |
| searches for any one of a set of elements (fonction gnrique) | |
trouve la premire position dans laquelle deux plages diffrentes Original: finds the first position where two ranges differ The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (fonction gnrique) | |
recherches pour une srie d'lments Original: searches for a range of elements The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (fonction gnrique) | |