dummy_A Node1 dummy_A + dummy_A() + ~dummy_A() + dummy() Node2 std::vector< dummy_B > Node2->Node1 -m_dummy Node3 dummy_B + dummy_B() + ~dummy_B() + dummy() Node3->Node2 +elements Node4 std::vector< dummy_C > Node4->Node3 -m_dummy Node5 dummy_C - m_dummy + dummy_C() + ~dummy_C() + value() Node5->Node4 +elements