C12313211232233312111111312111133133313331323133313333232233221122212121   >>    C1231321123223331211111131211113313331333132313331333323223322112221212   <<    C12313211232233312111111312111133133313331323133313333232233221122212123   >>      C12313211232233312111111312111133133313331323133313333232233221122212122   >>