template<class InputIter, class OutputIter, class UnaryPredicate>
constexpr OutputIter
copy_if(InputIter first, InputIter last, OutputIter out, UnaryPredicate pred);

template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class UnaryPredicate>
ForwardIt2 copy_if(ExecutionPolicy&& policy, ForwardIt1 first,
                    ForwardIt1 last, ForwardIt2 d_first,
                    UnaryPredicate pred);

#include <iostream>
#include <algorithm>
#include <string>
#include <vector>

int main()
{
    auto data = {1, 2, 3, 5, 7};
    std::vector<int> v(4);ф

    // скопирует только нечетные элементы
    auto it = std::copy_if(std::begin(data), std::end(data), std::begin(v), [](auto value) {
        return value % 2 != 0;
    });
    for (auto x : v)
    {
        std::cout << x << std::endl;
    }
    return 0;
}

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