Create a c ++ iterator to cycle through a hash table (Separate Chaining)

I'm new to c ++ and I'm not able to create an iterator to traverse a hash table. The table is composed of a vector of n linked list positions (created by me). I need an iterator to go from beginning to end, line by line, to be able to access each one. ( I do not want the code, only guidelines ). As a matter of curiosity, each in the list represents a vertex in a graph, to make a search in depth or width, precise runs vertex by vertex, hence the need of the iterator  The list is implemented like this:

class ListVertices
{
public:
    ListVertices();
    ~ListVertices();
    void put(const int& v);
    void del(const int& v);
    Vertice* get(const int& v);
    void imprime() const;

private:
    Vertice* first; // ponteiro para o primeiro no
    Vertice* getNewVertice(const int& v, Vertice* _next);

};

And the hash table:

class Hashtable
{
public:
    Hashtable(const int& _n);
    ~Hashtable();
    void putKey(const int& key);  /// insere uma chave na tabela
    void removeKey(const int key);                 /// remove uma chave na tabela
    Vertice* getkey(const int& key);               /// retorna um ponteiro para o vertice com id = _key
    void print();

private:
    int n;    /// quantidade de chaves
    int m;    /// tamanho da tabela
    ListVertices *table;  /// vetor de listas ligadas

    /// Funções utilitárias
    int hash(const int& key);             /// devolve um posiçao na tabela entre 0 e m-1(inclusive)
    int sizeTable();                       /// calcula o tamanho da tabela
    void resizeTable( const int& newSize); /// redimensiona o tamanho da tabela

};