KEY getKey();

VALUE getValue();

friend class HashMap<KEY, VALUE>;

Node():next(NULL), key(), value() {}

Node(const KEY &k, const VALUE &v): key(k), value(v), next(NULL) {}

~Node() {

if (next) delete next;

}

KEY key;

VALUE value;

Node *next;

HashMap();

int size();

bool empty();

int insert(KEY, VALUE);

Node<KEY, VALUE> *find(KEY);

int erase(KEY);

void clear();

VALUE &operator [] (const KEY&);

unsigned long long HashValue(KEY);

std::vector<Node<KEY, VALUE>*> head;

int n;