std::all_of, std::any_of, std::none_of
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| Definido no cabeçalho <algorithm>
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| template< class InputIt, class UnaryPredicate > bool all_of( InputIt first, InputIt last, UnaryPredicate p ); |
(1) | (desde C++11) |
| template< class InputIt, class UnaryPredicate > bool any_of( InputIt first, InputIt last, UnaryPredicate p ); |
(2) | (desde C++11) |
| template< class InputIt, class UnaryPredicate > bool none_of( InputIt first, InputIt last, UnaryPredicate p ); |
(3) | (desde C++11) |
Verifica se predicado unário
2) p retornos true para todos os elementos no intervalo [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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Verifica se predicado unário
3) p retornos true de pelo menos um elemento na faixa [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.
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Verifica se predicado unário
p retornos true para não elementos no intervalo [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.
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Índice |
[editar] Parâmetros
| first, last | - | a gama de elementos para examinar
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 | - | unary predicate . The signature of the predicate function should be equivalent to the following: bool pred(const Type &a); The signature does not need to have const &, but the function must not modify the objects passed to it. |
| Type requirements | ||
-InputIt must meet the requirements of InputIterator.
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[editar] Valor de retorno
1)true se unário predicado true retornos para todos os elementos da gama, false contrário. Retorna true se o intervalo é vazio.
2) 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.
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true se unário predicado true retornos para pelo menos um elemento em faixa, false contrário. Retorna false se o intervalo é vazio.
3) 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.
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true se unário predicado true retorna para nenhum elemento da gama, false contrário. Retorna true se o intervalo é vazio.
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.
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[editar] Complexidade
No máximo
last - first aplicações do predicadoOriginal:
At most
last - first applications of the predicateThe text has been machine-translated via Google Translate.
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[editar] Possível implementação
| First version |
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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; } |
[editar] Exemplo
#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"; } }
Saída:
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
