C12313211232233312111111312111133133313331323133313332322331212222123132212221   >>    C1231321123223331211111131211113313331333132313331333232233121222212313221222   <<    C12313211232233312111111312111133133313331323133313332322331212222123132212223   >>      C12313211232233312111111312111133133313331323133313332322331212222123132212222   >>