filter return new element list

pr6.cpp

@@ -7,13 +7,14 @@ template<class T>
 class Element {
 protected:
     Element* next;
+    Element* prev;
     T info;
 
 public:
-    Element() : next(nullptr), info(T()) {}
+    Element() : next(nullptr), prev(nullptr), info(T()) {}
-    Element(const T& data) : next(nullptr), info(data) {}
+    Element(const T& data) : next(nullptr), prev(nullptr), info(data) {}
-    Element(Element* Next, const T& data) : next(Next), info(data) {}
+    Element(Element* Next, Element* Prev, const T& data) : next(Next), prev(Prev), info(data) {}
-    Element(const Element& el) : next(el.next), info(el.info) {}
+    Element(const Element& el) : next(el.next), prev(el.prev), info(el.info) {}
 
     template<class T1>
     friend ostream& operator<<(ostream& s, const Element<T1>& el);
@@ -26,10 +27,18 @@ public:
         return next;
     }
 
+    Element* getPrev() const {
+        return prev;
+    }
+
     void setNext(Element* nextElement) {
         next = nextElement;
     }
 
+    void setPrev(Element* prevElement) {
+        prev = prevElement;
+    }
+
     template<class T1> friend class LinkedList;
 };
 
@@ -65,8 +74,32 @@ public:
         head = tail = nullptr;
         count = 0;
     }
+
+    Element<T>& operator[](int index) {
+        if (index < 0 || index >= count) {
+            throw out_of_range("Index out of range");
+        }
+        Element<T>* current = head;
+        for (int i = 0; i < index; ++i) {
+            current = current->getNext();
+        }
+        return *current;
+    }
+
+    template<class T1>
+    friend ostream& operator<<(ostream& s, const LinkedList<T1>& list);
 };
 
+template<class T1>
+ostream& operator<<(ostream& s, const LinkedList<T1>& list) {
+    Element<T1>* current = list.head;
+    while (current != nullptr) {
+        s << current->getInfo() << " ";
+        current = current->getNext();
+    }
+    return s;
+}
+
 template<class T>
 class SinglyLinkedListStack : public LinkedList<T> {
 public:
@@ -111,9 +144,10 @@ public:
 };
 
 template<class T>
-class SinglyLinkedListQueue : public LinkedList<T> {
+class DoublyLinkedListStack : public SinglyLinkedListStack<T> 
+{
 public:
-    SinglyLinkedListQueue() : LinkedList<T>() {}
+    DoublyLinkedListStack() : SinglyLinkedListStack<T>() {}
 
     virtual Element<T>* push(const T& value) override {
         Element<T>* newElement = new Element<T>(value);
@@ -122,6 +156,7 @@ public:
         }
         else {
             this->tail->setNext(newElement);
+            newElement->setPrev(this->tail);
             this->tail = newElement;
         }
         this->count++;
@@ -129,56 +164,182 @@ public:
     }
 
     virtual Element<T>* pop() override {
-        if (this->head == nullptr)
+        if (this->tail == nullptr)
             return nullptr;
 
-        Element<T>* res = this->head;
+        Element<T>* res = this->tail;
 
         if (this->head == this->tail) {
             this->head = this->tail = nullptr;
         }
         else {
-            this->head = this->head->getNext();
+            this->tail = this->tail->getPrev();
+            if (this->tail) {
+                this->tail->setNext(nullptr);
+            }
         }
 
         this->count--;
         return res;
     }
 
-    virtual ~SinglyLinkedListQueue() { cout << "\nSinglyLinkedListQueue class destructor\n"; }
+            Element<T>*insert(const T & value, int position) {
-};
+            if (position < 0 || position > this->count) {
+                throw out_of_range("Index out of range");
+            }
 
-template<class T>
+            Element<T>* newElement = new Element<T>(value);
-class StackQueue : protected SinglyLinkedListStack<T>, protected SinglyLinkedListQueue<T> {
-public:
-    StackQueue() : SinglyLinkedListStack<T>(), SinglyLinkedListQueue<T>() {}
 
-    Element<T>* push_back(const T& value) { return SinglyLinkedListQueue<T>::push(value); }
+            if (position == 0) {
-    Element<T>* push_front(const T& value) { return SinglyLinkedListStack<T>::push(value); }
+                newElement->setNext(this->head);
-    Element<T>* pop_back() { return SinglyLinkedListStack<T>::pop(); }
+                if (this->head != nullptr) {
-    Element<T>* pop_front() { return SinglyLinkedListQueue<T>::pop(); }
+                    this->head->setPrev(newElement);
-
+                }
-    using LinkedList<T>::isEmpty;
+                this->head = newElement;
-};
+                if (this->count == 0) {
-
+                    this->tail = newElement;
-int main() {
+                }
-    StackQueue<int> stackQueue;
+            }
-
+            else {
-    // Добавление элементов в конец и начало списка
+                Element<T>* current = this->head;
-    stackQueue.push_back(1);
+                for (int i = 0; i < position - 1; ++i) {
-    stackQueue.push_back(2);
+                    current = current->getNext();
-    stackQueue.push_front(3);
+                }
-    stackQueue.push_front(4);
+                newElement->setNext(current->getNext());
-
+                newElement->setPrev(current);
-    // Удаление элементов с начала и конца списка
+                if (current->getNext() != nullptr) {
-    while (!stackQueue.isEmpty()) {
+                    current->getNext()->setPrev(newElement);
-        Element<int>* elem = stackQueue.pop_back();
+                }
-        if (elem) {
+                current->setNext(newElement);
-            cout << elem->getInfo() << " ";
+                if (newElement->getNext() == nullptr) {
-            delete elem;
+                    this->tail = newElement;
+                }
+            }
+            this->count++;
+            return newElement;
         }
-    }
-    cout << endl;
 
-    return 0;
+        bool remove(const T & value) {
-}
+            Element<T>* current = this->head;
+            while (current != nullptr) {
+                if (current->getInfo() == value) {
+                    if (current == this->head) {
+                        this->head = current->getNext();
+                        if (this->head != nullptr) {
+                            this->head->setPrev(nullptr);
+                        }
+                    }
+                    else if (current == this->tail) {
+                        this->tail = current->getPrev();
+                        if (this->tail != nullptr) {
+                            this->tail->setNext(nullptr);
+                        }
+                    }
+                    else {
+                        current->getPrev()->setNext(current->getNext());
+                        current->getNext()->setPrev(current->getPrev());
+                    }
+                    delete current;
+                    this->count--;
+                    return true;
+                }
+                current = current->getNext();
+            }
+            return false;
+        }
+
+        Element<T>* find(const T & value) {
+            Element<T>* current = this->head;
+            while (current != nullptr) {
+                if (current->getInfo() == value) {
+                    return current;
+                }
+                current = current->getNext();
+            }
+            return nullptr;
+        }
+
+        LinkedList<T> filter(const T & value, char condition) {
+            LinkedList<T> filteredList;
+            Element<T>* current = this->head;
+            while (current != nullptr) {
+                if (condition == '>' && current->getInfo() > value) {
+                    filteredList.push(current->getInfo());
+                }
+                else if (condition == '<' && current->getInfo() < value) {
+                    filteredList.push(current->getInfo());
+                }
+                current = current->getNext();
+            }
+            return filteredList;
+        }
+
+
+        Element<T>* search(const T & value) {
+            Element<T>* current = this->head;
+            while (current != nullptr) {
+                if (current->getInfo() == value) {
+                    return current;
+                }
+                current = current->getNext();
+            }
+            return nullptr;
+        }
+
+        virtual ~DoublyLinkedListStack() { cout << "\nDoublyLinkedListStack class destructor\n"; }
+    };
+
+    int main() {
+        DoublyLinkedListStack<int> doublyStack;
+
+        // Добавление элементов в стек
+        doublyStack.push(1);
+        doublyStack.push(2);
+        doublyStack.push(3);
+        doublyStack.push(4);
+
+        // Вывод элементов с помощью перегруженного оператора <<
+        cout << doublyStack << endl;
+
+        // Доступ к элементам через перегруженный оператор []
+        try {
+            cout << "Element at index 2: " << doublyStack[2].getInfo() << endl;
+        }
+        catch (const out_of_range& e) {
+            cout << e.what() << endl;
+        }
+
+        // Вставка элемента
+        doublyStack.insert(5, 2);
+        cout << doublyStack << endl;
+
+        // Поиск элемента
+        Element<int>* foundElement = doublyStack.find(3);
+        if (foundElement) {
+            cout << "Found element: " << foundElement->getInfo() << endl;
+        }
+        else {
+            cout << "Element not found" << endl;
+        }
+
+        // Удаление элемента
+        if (doublyStack.remove(2)) {
+            cout << "Element removed successfully" << endl;
+        }
+        else {
+            cout << "Element not found" << endl;
+        }
+        cout << doublyStack << endl;
+
+        // Удаление элементов из стека
+        while (!doublyStack.isEmpty()) {
+            Element<int>* elem = doublyStack.pop();
+            if (elem) {
+                cout << elem->getInfo() << " ";
+                delete elem;
+            }
+        }
+        cout << endl;
+
+        return 0;
+    }