D1212132333131322331323331313131323132313331312323223313232212121   >>    D121213233313132233132333131313132313231333131232322331323221212   <<    D1212132333131322331323331313131323132313331312323223313232212123   >>      D1212132333131322331323331313131323132313331312323223313232212122   >>