#include <iostream>
#include <vector>
#include <functional>

template <typename iter, typename Fun>
void myapply(iter start, iter end, Fun func) {
    std::vector<std::reference_wrapper<typename iter::value_type>> v(start, end);
    auto it = v.begin();
    while (it != v.end()) {
        func(*it);
        it++;
    }
}

template<typename Cmp, typename iter>
std::vector<typename iter::value_type> myfilter2(iter start, iter end, Cmp pred) {
    std::vector<typename iter::value_type> ans;
    std::vector<std::reference_wrapper<typename iter::value_type>> v(start, end);
    for (const auto& it: v) {
        if (pred(it)) {
            ans.insert(ans.end(), it);
        }
    }
    return ans;
}

template <typename iter, typename Fun>
void myapply(iter* start, iter* end, Fun func) {
    std::vector<std::reference_wrapper<iter>> v(start, end);
    auto it = v.begin();
    while (it != v.end()) {
        func(*it);
        it++;
    }
}

template<typename Cmp, typename iter>
std::vector<iter> myfilter2(iter* start, iter* end, Cmp pred) {
    std::vector<iter> ans;
    std::vector<std::reference_wrapper<iter>> v(start, end);
    for (const auto& it: v) {
        if (pred(it)) {
            ans.insert(ans.end(), it);
        }
    }
    return ans;
}