fix removeState, rm addState, add pop override to fit inheritence

pr6.cpp

@@ -1,6 +1,9 @@
 #include <iostream>
 #include <stdexcept>
 #include <functional>
+#include <fstream>
+#include <sstream>
+#include <string>
 
 using namespace std;
 
@@ -35,6 +38,8 @@ public:
         next = nextElement;
     }
 
+    virtual ~Element() {}
+
     template<class T1> friend class LinkedList;
     template<class T1> friend class DoublyLinkedStack;
     template<class T1> friend ostream& operator<<(ostream& s, const Element<T1>& el);
@@ -216,7 +221,9 @@ public:
         if (this->tail == nullptr)
             return nullptr;
 
-        DoublyLinkedElement<T>* res = static_cast<DoublyLinkedElement<T>*>(this->tail);
+        //DoublyLinkedElement<T>* res = static_cast<DoublyLinkedElement<T>*>(this->tail);
+        // Преобразование указателя на базовый класс в указатель на производный класс
+        DoublyLinkedElement<T>* res = dynamic_cast<DoublyLinkedElement<T>*>(this->tail);
 
         if (this->head == this->tail) {
             this->head = this->tail = nullptr;
@@ -401,20 +408,45 @@ public:
     // geters
     string getName() const { return name; }
     double getArea() const { return area; }
+    long getPopulation() const { return population; }
+    string getCapital() const { return capital; }
+    string getLanguage() const { return language; }
+
 };
 
 
-class StateList {
+class StateList : public DoublyLinkedStack<State> {
 protected:
     SinglyLinkedListQueue<State> stateList;
 
 public:
     // Добавление нового государства в начало списка
-    void addState(const State& state) {
+    //void addState(const State& state) {
+    //    stateList.push(state);
+    //}
+    virtual Element<State>* push(const State& state) override {
         stateList.push(state);
+        return stateList.getHead();
+    }
+    friend ostream& operator<<(ostream& os, const StateList& stateList) {
+        Element<State>* current = stateList.stateList.getHead();
+        while (current != nullptr) {
+            os << current->getInfo() << endl;
+            current = current->getNext();
+        }
+        return os;
     }
 
     // Удаление государства из начала списка
+    virtual Element<State>* pop() override {
+        try {
+            return new Element<State>(removeState());
+        }
+        catch (const logic_error& e) {
+            cout << e.what() << endl;
+            return nullptr;
+        }
+    }
     State removeState() {
         Element<State>* element = stateList.pop();
         if (element) {
@@ -424,7 +456,6 @@ public:
         }
         throw logic_error("State list is empty");
     }
-
     // Поиск государства по названию
     State* findStateByName(const string& name) {
         Element<State>* current = stateList.getHead();
@@ -434,7 +465,6 @@ public:
             }
             current = current->getNext();
         }
-        /*throw logic_error("State not found");*/
         return nullptr;
     }
 
@@ -449,8 +479,73 @@ public:
             current = current->getNext();
         }
     }
+
+    // Универсальная фильтрация государств по произвольному условию
+    void printStatesByCondition(function<bool(const State&)> condition) {
+        Element<State>* current = stateList.getHead();
+        while (current != nullptr) {
+            const State& state = current->getInfo();
+            if (condition(state)) {
+                cout << state << endl;
+            }
+            current = current->getNext();
+        }
+    }
+
+    // Сохранение списка состояний в файл
+    void save(const string& filename) const {
+        ofstream outputFile(filename);
+        if (!outputFile.is_open()) {
+            throw runtime_error("Unable to open file for writing");
+        }
+
+        Element<State>* current = stateList.getHead();
+        while (current != nullptr) {
+            outputFile << current->getInfo().getName() << ","
+                << current->getInfo().getCapital() << ","
+                << current->getInfo().getLanguage() << ","
+                << current->getInfo().getPopulation() << ","
+                << current->getInfo().getArea() << endl;
+            current = current->getNext();
+        }
+
+        outputFile.close();
+    }
+
+    // Загрузка списка состояний из файла
+    void load(const string& filename) {
+        ifstream file(filename);
+        if (file.is_open()) {
+            // Очищаем текущий список состояний перед загрузкой новых данных
+            while (!stateList.isEmpty()) {
+                stateList.pop();
+            }
+
+            string line;
+            while (getline(file, line)) {
+                stringstream ss(line);
+                string name, capital, language;
+                long population;
+                double area;
+                getline(ss, name, ',');
+                getline(ss, capital, ',');
+                getline(ss, language, ',');
+                ss >> population;
+                ss.ignore(1); // Ignore the comma
+                ss >> area;
+                State state(name, capital, language, population, area);
+                stateList.push(state);
+            }
+            file.close();
+        }
+        else {
+            cout << "Unable to open file for loading" << endl;
+        }
+    }
 };
 
+
+
 int main() {
     DoublyLinkedStack<int> stack;
 
@@ -501,25 +596,34 @@ int main() {
     }
     cout << endl;
 
-    //StateList
-    StateList states;
 
-    // Пример использования
-    states.addState(State("USA", "Washington D.C.", "English", 328000000, 9833510));
-    states.addState(State("India", "New Delhi", "Hindi", 1380000000, 3287263));
-    //stateList.addState(usa);
-    //stateList.addState(india);
+    StateList* states = new StateList();
+ 
+    //for 6.2
+    states->push(State("USA", "Washington D.C.", "English", 328000000, 9833510));
+    states->push(State("India", "New Delhi", "Hindi", 1380000000, 3287263));
+
+    // Сохраняем список состояний в файл
+    states->save("states.txt");
+
+    // Загружаем список состояний из файла
+    StateList loadedStates;
+    loadedStates.load("states.txt");
 
     cout << "List of states:" << endl;
-    cout << states.findStateByName("USA") << endl;
+    //cout << states->findStateByName("USA") << endl;
+    cout << loadedStates << endl;
 
-    //cout << "Removing state:" << endl;
-    //cout << stateList.removeState() << endl;
+    cout << "States with area between 9800500 and 9987263:" << endl;
+    states->printStatesByArea(9800500, 9987263);
 
-    cout << "States with area between 2000 and 3000:" << endl;
-    states.printStatesByArea(2000, 3000);
+    cout << "States with population greater than 1 billion:" << endl;
+    states->printStatesByCondition([](const State& state) 
+        {
+        return state.getPopulation() > 1000000000;
+        });
 
-    State* foundState = states.findStateByName("USA");
+    State* foundState = states->findStateByName("USA");
     if (foundState) {
         cout << "Found state: " << *foundState << endl;
     }
@@ -528,7 +632,7 @@ int main() {
     }
 
     try {
-        State removedState = states.removeState();
+        State removedState = states->removeState();
         cout << "Removed state: " << removedState << endl;
     }
     catch (const out_of_range& e) {
@@ -536,9 +640,10 @@ int main() {
     }
 
     cout << "States after removal:" << endl;
-    states.printStatesByArea(0, 10000);
-
+    states->printStatesByArea(0, 10000000);
 
+    // Освобождение памяти, выделенной для объекта StateList
+    delete states;
 
     return 0;
 }