-ic bbb bbc bbd bbe bbi bbk bcb bcc bcd bce bci bck bdb bdc bdd bde bdi bdk be- beb bec bed bee bei bek bi- bib bic bid bie bii bik bkb bkc bke bkk c-- cbb cbc cbd cbe cbi cbk ccb ccc ccd cce cci cck cdb cdc cdd cde cdi cdk ce- ceb cec ced cee cei cek ci- cib cic cid cie cii cik ckb ckc ckd cki dbb dbc dbd dbe dbi dbk dcb dcc dcd dce dci dck ddb ddc ddd dde ddi ddk de- deb dec ded dee dei dek di- dib dic did die dii dik dkb dkc dke dki dkk ebb ebc ebd ebe ebi ebk ec- ecb ecc ecd ece eci eck ed- edb edc edd ede edi edk eeb eec eed eee eek eib eic eid eie eii eik ekb ekc ekd eke eki i-d ibb ibc ibd ibe ibi ibk icb icc icd ice ici ick idb idc idd ide idi idk ie- iec ied iee iei iek iib iic iid iie iii ikb ikc ike iki ikk kbb kbc kbd kbe kbi kbk kcb kcc kcd kce kci kck kdb kdc kde kdk ke- keb kec ked kee kei kek kib kic kid kie kii kik kkb kkc kke kki kkk