a-be aaaa aaab aaad aaae aaap aaba aabb aabd aabp aada aade aaea aaep aapa abaa abab abad abae abap abb- abba abbb abbe abda abed abee abpa abpd abpp adaa adab adad adae adap adba adda addd adde adea adeb adee adp- aeap aede apap apba apda apdd apea aped apep appa appd baaa baad baba babb babe bada badb badd bade baed bapa bape bapp bbad bbbb bbdd bbeb bead beap beba bebb bebe beda bede beeb beed beep bpda bpea daab daad daae daap daba dabb dabp dada dade daeb dapa dape dapp dbpd dddd dead deae deap deba debe deda dedd dede deeb deed deep depa depe depp dpaa dppa eaba eada eadb eadd eadp eapp ebba ebed edad edda edde eddp ede- edea eede eeea eeee epaa epad epee eppa eppp paap paba pada padd pade paea paep papa papb pape papp pbed pbpa pdea pdpa peab peap peba ped- peda pede peed peep pepa pepd pepe ppad ppap pppa pppd pppp