#include<iostream>
using namespace std;

class simpleItem {
public:
	simpleItem() {};
	virtual ~simpleItem() {};
	virtual bool ordineInverso() = 0;
	virtual void visualizza() = 0;
};

class intItem: public simpleItem {
private:
	int data;
public:
	intItem(int i): data(i) {};
	bool ordineInverso() override {
		return data%2;	// i numero dispari vanno in ordine inverso
	};
	void visualizza() override {
		cout << data<<" ";
	};
};

class charItem: public simpleItem {
private:
	char data;
public:
	charItem(char c): data(c) {};
	bool ordineInverso() override {
		return (data=='a'||data=='e'||data=='i'||data=='o'||data=='u');
				// le vocali vanno in ordine inverso
	};
	void visualizza() override {
		cout << data <<" ";
	}
};

class simpleNode {
public:
	simpleItem *item;
	simpleNode *next;
	simpleNode(simpleItem *i): item(i), next(nullptr) {};
	~simpleNode() {};
};

class simpleList {
private:
	simpleNode *head;
	simpleNode *tail;
public:
	simpleList(): head(nullptr), tail(nullptr) {};
	~simpleList();
	bool isEmpty();
	simpleList *HInsert(simpleItem *);
	simpleItem *HRemove();
	simpleList *TInsert(simpleItem *);
	simpleItem *TRemove();
};