public function getVertexLast()
    {
        if (!$this->vertices) {
            throw new UnderflowException('Does not contain any vertices');
        }
        end($this->vertices);

        return current($this->vertices);
    }
public function getVertexLast()
    {
        if (!$this->vertices) {
            throw new UnderflowException('Does not contain any vertices');
        }
        end($this->vertices);

        return current($this->vertices);
    }
public function getVertexLast ( ) { if ( ! $ this -> vertices ) { throw new UnderflowException ( 'Does not contain any vertices' ) ; } end ( $ this -> vertices ) ; return current ( $ this -> vertices ) ; }
return last Vertex in this set of Vertices

@return Vertex             last Vertex in this set of Vertices
@throws UnderflowException if set is empty
return last Vertex in this set of Vertices