std::all_of, std::any_of, std::none_of
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<metanoindex/>
<tbody> </tbody>| Dclar dans l'en-tte <algorithm>
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template< class InputIt, class UnaryPredicate > bool all_of( InputIt first, InputIt last, UnaryPredicate p ); |
(1) | (depuis C++11) |
template< class InputIt, class UnaryPredicate > bool any_of( InputIt first, InputIt last, UnaryPredicate p ); |
(2) | (depuis C++11) |
template< class InputIt, class UnaryPredicate > bool none_of( InputIt first, InputIt last, UnaryPredicate p ); |
(3) | (depuis C++11) |
1)
Vrifie si prdicat unaire
p retours true pour tous les lments de la gamme [first, last) .Original:
Checks if unary predicate
p returns true for all elements in the range [first, last).The 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.
2)
Vrifie si prdicat unaire
p retours true pour au moins un lment dans la gamme [first, last) .Original:
Checks if unary predicate
p returns true for at least one element in the range [first, last).The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
3)
Vrifie si prdicat unaire
p retours true pour aucun des lments de la gamme [first, last) .Original:
Checks if unary predicate
p returns true for no elements in the range [first, last).The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
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. |
| p | - | prdicat unaire . L'expression |
| Type requirements | ||
-InputIt must meet the requirements of InputIterator.
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Retourne la valeur
1)
true si prdicat unaire renvoie true pour tous les lments de la gamme, false autrement. Retours true si la plage est vide .Original:
true if unary predicate returns true for all elements in the range, false otherwise. Returns true if the range is empty.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
2)
true si prdicat unaire renvoie true pendant au moins un lment de la gamme, false autrement. Retours false si la plage est vide .Original:
true if unary predicate returns true for at least one element in the range, false otherwise. Returns false if the range is empty.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
3)
true si prdicat unaire renvoie true pour aucun des lments de la gamme, false autrement. Retours true si la plage est vide .Original:
true if unary predicate returns true for no elements in the range, false otherwise. Returns true if the range is empty.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
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.
You can help to correct and verify the translation. Click here for instructions.
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Mise en uvre possible
| First version |
|---|
template< class InputIt, class UnaryPredicate >
bool all_of(InputIt first, InputIt last, UnaryPredicate p)
{
for (; first != last; ++first) {
if (!p(*first)) return false;
}
return true;
}
|
| Second version |
template< class InputIt, class UnaryPredicate >
bool any_of(InputIt first, InputIt last, UnaryPredicate p)
{
for (; first != last; ++first) {
if (p(*first)) return true;
}
return false;
}
|
| Third version |
template< class InputIt, class UnaryPredicate >
bool none_of(InputIt first, InputIt last, UnaryPredicate p)
{
for (; first != last; ++first) {
if (p(*first)) return false;
}
return true;
}
|
Exemple
#include <vector>
#include <numeric>
#include <algorithm>
#include <iterator>
#include <iostream>
#include <functional>
int main()
{
std::vector<int> v(10, 2);
std::partial_sum(v.cbegin(), v.cend(), v.begin());
std::cout << "Among the numbers: ";
std::copy(v.cbegin(), v.cend(), std::ostream_iterator<int>(std::cout, " "));
std::cout << '\n';
if (std::all_of(v.cbegin(), v.cend(), [](int i){ return i % 2 == 0; })) {
std::cout << "All numbers are even\n";
}
if (std::none_of(v.cbegin(), v.cend(), std::bind(std::modulus<int>(),
std::placeholders::_1, 2))) {
std::cout << "None of them are odd\n";
}
struct DivisibleBy
{
const int d;
DivisibleBy(int n) : d(n) {}
bool operator()(int n) const { return n % d == 0; }
};
if (std::any_of(v.cbegin(), v.cend(), DivisibleBy(7))) {
std::cout << "At least one number is divisible by 7\n";
}
}
Rsultat :
Among the numbers: 2 4 6 8 10 12 14 16 18 20
All numbers are even
None of them are odd
At least one number is divisible by 7