D1212121212131323223313233231323133313231323331311331323132211231   >>    D121212121213132322331323323132313331323132333131133132313221123   <<    D1212121212131323223313233231323133313231323331311331323132211233   >>      D1212121212131323223313233231323133313231323331311331323132211232   >>