C212212121212113313221323131323132313132322331323222313232212121   >>    C21221212121211331322132313132313231313232233132322231323221212   <<    C212212121212113313221323131323132313132322331323222313232212123   >>      C212212121212113313221323131323132313132322331323222313232212122   >>