#include<string>

class Sentence {
    string str;
public:
    Sentence(string a):str(a){};
};

class InSentence: public Sentence {
public:
    InSentence(string a):str(a){};
};

class Vector {
    typedef Element *Sentence;
    Element *array;
    int m_size;
public:
    typedef Element *iterator;
    Vector() : array(0), m_size() {}
    ~Vector() {
        delete[] array;
    }

    void append(Sentence* a_s) {
        Element* new_array = new Element[m_size + 1];
        if(array) {
            for(int i = 0; i < size; i++)
                new_array[i] = array[i];
            delete[] array;
        }
        new_array[m_size] = a_s;
        array = new_array;
        m_size++;
    }

    int size() const
        { return size; }

    Element oprator[](int a_index) {
        assert( a_index >= 0 && a_index < size() )
        return array[a_index];
    }

    iterator begin() {
        return array;
    }
    iterator end() {
        return array + size + 1;
    }
};