a-a a-b a-c aaa aab aac aad aap aas ab- aba abb abc abd abp abs ac- aca acb acc acd acp acs ad- ada adb adc add adp ads ap- apa apb apc apd app aps as- asa asb asc asd asp ass b-p baa bab bac bad bap bas bba bbb bbc bbd bbp bbs bca bcb bcc bcd bcp bcs bda bdb bdc bdd bdp bds bpa bpb bpc bpd bpp bps bsa bsb bsc bsd bsp bss c-- caa cab cac cad cap cas cba cbb cbc cbd cbp cbs cca ccb ccc ccd ccp ccs cda cdb cdc cdd cdp cds cpa cpb cpc cpd cpp cps csa csb csc csd csp css daa dab dac dad dap das dba dbb dbc dbd dbp dbs dca dcb dcc dcd dcp dcs dda ddb ddc ddd ddp dds dpa dpb dpc dpd dpp dps dsa dsb dsc dsd dsp dss p-p paa pab pac pad pap pas pba pbb pbc pbd pbp pbs pca pcb pcc pcd pcp pcs pda pdb pdc pdd pdp pds ppa ppb ppc ppd ppp pps ps- psa psb psc psd psp pss saa sab sac sad sap sas sba sbb sbc sbd sbp sbs sca scb scc scd scp scs sda sdb sdc sdd sdp sds spa spb spc spd spp sps ss- ssa ssb ssc ssd ssp sss