C131121333133313233213331333133313331333133313231323221323123121   >>    C13112133313331323321333133313331333133313331323132322132312312   <<    C131121333133313233213331333133313331333133313231323221323123123   >>      C131121333133313233213331333133313331333133313231323221323123122   >>