Практика 10

integer_set.cpp

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

class integer_set {
public:
    using const_iterator = std::vector<int>::const_iterator;

    integer_set() { }

    integer_set(const std::vector<int>& numbers)
        : container_(numbers)
    {
        std::sort(container_.begin(), container_.end());
        std::vector<int>::iterator end = std::unique(container_.begin(), container_.end());
        container_.resize(end - container_.begin());
        container_.shrink_to_fit();
    }

    const std::vector<int>& container() const {
        return container_;
    }

    bool has_element(int element) const {
        return std::binary_search(container_.begin(), container_.end(), element);
    }

    integer_set operator& (const integer_set& rhs) const {
        integer_set result;
        std::set_intersection(container_.begin(), container_.end(),
                              rhs.container_.begin(), rhs.container_.end(),
                              std::back_inserter(result.container_));
        return result;
    }

    integer_set operator| (const integer_set& rhs) const {
        integer_set result;
        std::set_union(container_.begin(), container_.end(),
                       rhs.container_.begin(), rhs.container_.end(),
                       std::back_inserter(result.container_));
        return result;
    }

    const_iterator begin() const {
        return container_.begin();
    }

    const_iterator end() const {
        return container_.end();
    }

private:
    std::vector<int> container_;
};

int main() {
    integer_set s1({1, 7, 9});
    integer_set s2({3, 0});
    integer_set s3({2, 3, 9});
    for (const int& element : s2 | s1 & s3) {
        std::cout << element << " ";
    }
    std::cout << std::endl;
    return 0;
}

swap.cpp

#include <vector>
#include <iostream>

int main() {
    std::vector<int> v(100 * 1000);
    for (int i = 0; i < 50 * 1000; i++) {
        v.pop_back();
    }
    std::vector<int>(v).swap(v);
    std::cout << v.capacity() << std::endl;
    return 0;
}