Лабораторные работы С++ (для ИВТ) / Готовые лабы С++ / Лаба1 / Laba 1 (8)

#include <iostream>
#include <windows.h>
using namespace std;

struct Node {
    double data;
    Node* next;
    
    Node(double val) : data(val), next(nullptr) {}
};

class CircularList {
private:
    Node* tail;
    
public:
    CircularList() : tail(nullptr) {
        cout << "Создан пустой кольцевой список" << endl;
    }
    
    void add(double value) {
        Node* newNode = new Node(value);
        if (!tail) {
            tail = newNode;
            tail->next = tail;
        } else {
            newNode->next = tail->next;
            tail->next = newNode;
            tail = newNode;
        }
        cout << "Добавлен элемент: " << value << endl;
    }
    
    bool remove(double value) {
        if (!tail) {
            cout << "Список пуст" << endl;
            return false;
        }
        
        Node* current = tail->next;
        Node* prev = tail;
        
        do {
            if (current->data == value) {
                prev->next = current->next;
                if (current == tail) {
                    if (current->next == current) tail = nullptr;
                    else tail = prev;
                }
                cout << "Удален элемент: " << value << endl;
                delete current;
                return true;
            }
            prev = current;
            current = current->next;
        } while (current != tail->next);
        
        cout << "Элемент " << value << " не найден" << endl;
        return false;
    }
    
    bool contains(double value) {
        if (!tail) {
            cout << "Список пуст" << endl;
            return false;
        }
        
        Node* current = tail->next;
        do {
            if (current->data == value) {
                cout << "Элемент " << value << " найден в списке" << endl;
                return true;
            }
            current = current->next;
        } while (current != tail->next);
        
        cout << "Элемент " << value << " не найден в списке" << endl;
        return false;
    }
    
    void print() {
        if (!tail) {
            cout << "Список пуст" << endl;
            return;
        }
        
        Node* current = tail->next;
        cout << "Элементы кольцевого списка: ";
        do {
            cout << current->data << " ";
            current = current->next;
        } while (current != tail->next);
        cout << endl;
    }
    
    ~CircularList() {
        if (!tail) return;
        
        Node* current = tail->next;
        while (current != tail) {
            Node* next = current->next;
            delete current;
            current = next;
        }
        delete tail;
        cout << "Список удален" << endl;
    }
};

int main() {
    SetConsoleOutputCP(65001);
    
    CircularList list;
    
    cout << "=== Работа с кольцевым списком ===" << endl;
    
    list.add(1.0);
    list.add(2.0);
    list.add(3.0);
    
    list.print();
    
    list.contains(2.0);
    list.contains(5.0);
    
    list.remove(2.0);
    list.print();
    
    list.remove(5.0); // Несуществующий элемент
    
    return 0;
}