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std::all_of, std::any_of, std::none_of - cppreference.com

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Definido no cabeçalho

<algorithm>

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)

1)

Verifica se predicado unário 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).

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2)

Verifica se predicado unário 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).

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3)

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).

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Parâmetros

first, last -

a gama de elementos para examinar

Original:

the range of elements to examine

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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.
The type Type must be such that an object of type InputIt can be dereferenced and then implicitly converted to Type. ​

Type requirements
-InputIt must meet the requirements of InputIterator.

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.

Original:

true if unary predicate returns true for all elements in the range, false otherwise. Returns true if the range is empty.

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2)

true se unário predicado true retornos para pelo menos um elemento em faixa, false contrário. Retorna false se o intervalo é vazio.

Original:

true if unary predicate returns true for at least one element in the range, false otherwise. Returns false if the range is empty.

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3)

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.

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Complexidade

No máximo last - first aplicações do predicado

Original:

At most last - first applications of the predicate

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Possível implementação

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;
}

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