#unclude<string>
....
class Sentence {
    string str;
public:
    Sentence(string a):str(a){};
};

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

struct stSentence {
    Sentence _str;
    stSentence* next;
    stSentence():_str(0),next(NULL){};
    stSentence(Sentence* str):_str(str),next(NULL){};
};

class Vector {
    stSentence* _stSen;
    int value;
public:
    void add_stSen(stSentence* stS){
        if(!_stStn) {
            _stStn = stS;
        else {
            stSentence* curr = new stSentence;
            curr = stS;
            curr->next = _stSen;
            _stS = curr;
        };
        value++;
    }

    Vector():_stSen(NULL),value(0);
    Vector(stSenstence* _stS) {
        add_stSen(_stS);
    }

    Vector(string str) {
        _len = strlen(str);
        if(str[_len]='?')
            Sentence* curr = new InSentence(str);
        else
            Sentence* curr = new Sentence(str);
        stSentence*curr = new stSentence;
        add_stSen(curr);
    }

    typedef int* iterator;
    iterator begin() {
        return _stStn;
    }
    iterator end() {
        return _stStn + value + 1;
    }
};