D1212121212131323131133132311233132322331323321211113313231231221   >>    D121212121213132313113313231123313232233132332121111331323123122   <<    D1212121212131323131133132311233132322331323321211113313231231223   >>      D1212121212131323131133132311233132322331323321211113313231231222   >>