26. Односвязный список

#include <iostream>
#include <string>

template<typename T>
class line {


    template<typename T>
    class element {
    public:
        T data;
        element<T> *next_element;
        element(T data = T(), element<T> *next_element = nullptr) {
            this->data = data;
            this->next_element = next_element;
        }
    };


    element<T> *first_element;
    unsigned int Size;
public:


    line() {
        Size = 0;
        first_element = nullptr;
    }


    int size() {
        return Size;
    }

    void push_back(T data) {
        if (first_element == nullptr) {
            first_element = new element<T>(data);
        }
        else {
            element <T> *temp_adress = first_element;
            while (!(temp_adress->next_element == nullptr)) {
                temp_adress = temp_adress->next_element;
            }
            temp_adress->next_element = new element<T>(data);
        }
        Size++;
    }


    T& operator[](const unsigned int index) {
        unsigned int Count = 0;
        element<T> *temp_adress = first_element;
        while (temp_adress->next_element != nullptr) {
            if (Count == index) {
                break;
            }
            temp_adress = temp_adress->next_element;
            Count++;
        }
        return temp_adress->data;
    }


    bool pop_front() {
        if (first_element != nullptr) {
            element<T> *temp_adress = first_element;
            first_element = first_element->next_element;
            delete temp_adress;
            Size--;
            return true;
        }
        else {
            std::cout << "Нечего удалять " << std::endl;
            return false;
        }
    }


    void clear() {
        while (pop_front());
    }


    ~line() {
        clear();
    }


    void push_front(T data) {
        first_element = new element<T>(data, first_element);
        Size++;
    }


    void pop_back() {
        unsigned int Count = 0;
        element<T> *temp_adress = first_element;
        while (Count != Size - 1) {
            temp_adress = temp_adress->next_element;
            Count++;
        }
        delete temp_adress->next_element;
        temp_adress->next_element = nullptr;
        Size--;
    }


    void insert(T data, const int index) {
        if (index == 0) {
            push_front(data);
        }
        else {
            unsigned int Count = 0;
            element<T> *temp_adress = first_element;
            while (Count != index - 1) {
                temp_adress = temp_adress->next_element;
                Count++;
            }
            element<T> *temp_adress_2 = temp_adress->next_element;
            temp_adress->next_element = new element<T>(data);
            temp_adress->next_element->next_element = temp_adress_2;
            Size++;
        }
    }


    void removeAt(const int index) {
        if (index == 0) {
            pop_front();
        }
        else if (index != Size - 1) {
            unsigned int Count = 0;
            element<T> *temp_adress = first_element;
            while (Count != index - 1) {
                temp_adress = temp_adress->next_element;
            }
            element<T> *temp_adress_2 = temp_adress->next_element->next_element;
            delete temp_adress->next_element;
            temp_adress->next_element = temp_adress_2;
            Size--;
        }
        else {
            pop_back();
        }
    }
};

int main() {
    setlocale(LC_ALL, "ru");
    line<int> object;
    for (int i = 0; i < 10; i++) {
        object.push_back(i);
    }
    std::cout << "Размер элементов равен " << object.size() << std::endl;
    for (int i = 0; i < object.size(); i++) {
        std::cout << object[i] << " ";
    }
    std::cout << std::endl;
    object.pop_back();
    std::cout << "Размер элементов равен " << object.size() << std::endl;
    for (int i = 0; i < object.size(); i++) {
        std::cout << object[i] << " ";
    }
    std::cout << std::endl;

    object.removeAt(1);
    std::cout << "Размер элементов равен " << object.size() << std::endl;
    for (int i = 0; i < object.size(); i++) {
        std::cout << object[i] << " ";
    }
    std::cout << std::endl;
    system("pause");
    return 0;
}