-ic a-a a-b a-c a-i aaa aab aac aai aap ab- aba abb abc abi abp ac- aca acb acc aci acp ai- aia aib aic aii aip ap- apa apb apc api app b-p baa bab bac bai bap bba bbb bbc bbi bbp bca bcb bcc bci bcp bi- bia bib bic bii bip bpa bpb bpc bpi bpp c-- caa cab cac cai cap cba cbb cbc cbi cbp cca ccb ccc cci ccp ci- cia cib cic cii cip cpa cpb cpc cpi cpp ia- iaa iab iac iai iap iba ibb ibc ibi ibp ica icb icc ici icp iia iib iic iii iip ipa ipb ipc ipi ipp p-p paa pab pac pai pap pba pbb pbc pbi pbp pca pcb pcc pci pcp pia pib pic pii pip ppa ppb ppc ppi ppp