-er -ic a-a a-b a-c a-i aaa aab aac aae aai aap aar ab- aba abb abc abe abi abp abr ac- aca acb acc ace aci acp acr aea aeb aec aee aei aep aer ai- aia aib aic aie aii aip air ap- apa apb apc ape api app apr ar- ara arb arc are ari arp arr b-p baa bab bac bae bai bap bar bba bbb bbc bbe bbi bbp bbr bca bcb bcc bce bci bcp bcr be- bea beb bec bee bei bep ber bi- bia bib bic bie bii bip bir bpa bpb bpc bpe bpi bpp bpr bra brb bre bri brp brr c-- caa cab cac cae cai cap car cba cbb cbc cbe cbi cbp cbr cca ccb ccc cce cci ccp ccr ce- cea ceb cec cee cei cep cer ci- cia cib cic cie cii cip cir cpa cpb cpc cpe cpi cpp cpr cra crb crc cre cri crp crr eaa eab eac eae eai eap ear eba ebb ebc ebe ebi ebp ebr ec- eca ecb ecc ece eci ecr eea eeb eec eee eep eer eia eib eic eie eii eip eir ep- epa epb epc epe epi epp epr era erb erc ere eri erp err ia- iaa iab iac iae iai iap iar iba ibb ibc ibe ibi ibp ibr ica icb icc ice ici icp icr ie- iea iec iee iei iep ier iia iib iic iie iii iip iir ipa ipb ipc ipe ipi ipp ipr ir- ira irb irc ire iri irp irr p-p paa pab pac pae pai pap par pba pbb pbc pbe pbi pbp pbr pca pcb pcc pce pci pcp pcr pea peb pec pee pei pep per pia pib pic pie pii pip pir ppa ppb ppc ppe ppi ppp ppr pra prb prc pre pri prp prr ra- raa rab rac rae rai rap rar rba rbb rbc rbe rbi rbp rbr rca rcb rcc rce rci rcp rcr re- rea reb rec ree rei rep rer ria rib ric rie rii rip rir rpa rpb rpc rpe rpi rpp rpr rra rrb rrc rri rrp rrr