rpn rpp rpr rpu rpz rra rrb rrc rri rrl rrn rrp rrr rru rua rub ruc rue rui run rup rur ruu ruz rza rzb rze ua- uaa uab uac uae uai ual uan uap uar uau uaz uba ubb ubc ube ubi ubl ubn ubp ubr ubu uca ucb ucc uce uci ucl ucn ucp ucr ucu uea ueb uec uee uei uel uen uep uer uia uib uic uie uii uil uin uip uir uiu ula ulb ulc ule uli ull uln ulp ulr ulu un- una unb unc une uni unl unn unp unr unu up- upa upb upc upe upi upn upp upr upu upz ur- ura urb urc ure uri url urn urp urr uru urz uua uuc uue uun uur uuu uza uzb uzi uzu zaa zab zac zai zan zap zar zaz zbb zbc zbl zbr zce zcl zea zeb zec zee zel zen zep zer zez zia zib zie zil zin zip zir ziz zla zlr znc zne znn znp zpc zpe zpi zpl zpp zpr zpu zrl zrp zub zuc zui zul zun zur zuz zzr zzz