-up b-p b-u bbb bbi bbp bbr bbu bi- bib bii bip bir biu bpb bpi bpp bpr bpu brb bri brp brr bru bub bui bup bur buu ibb ibi ibp ibr ibu iib iii iip iir iiu ipb ipi ipp ipr ipu ir- irb iri irp irr iru iu- iub iui iup iur p-p pbb pbi pbp pbr pbu pib pii pip pir piu ppb ppi ppp ppr ppu prb pri prp prr pru pub pui pup pur puu rbb rbi rbp rbr rbu rib rii rip rir rpb rpi rpp rpr rpu rrb rri rrp rrr rru rub rui rup rur ruu ubb ubi ubp ubr ubu uib uii uip uir uiu up- upb upi upp upr upu ur- urb uri urp urr uru uur uuu