iii iio iip iir iis iix io- ioi ioo iop ior ios ipi ipo ipp ipr ips ipx ipy ir- iri iro irp irr irs irx iry is- isi iso isp isr iss isy ixi ixy iyo iyr iys iyy o-i oii oio oip oir ois oo- ooi ooo oop oor oos oox op- opi opo opp opr ops opx opy or- ori oro orp orr ors orx ory os- osi oso osp osr oss osx ox- oxi oxo oxx oxy oyi oyo oys p-p pii pio pip pir pis pix poi poo pop por pos pox poy ppi ppo ppp ppr pps ppx pri pro prp prr prs prx pry ps- psi pso psp psr pss psx psy pxr pxs py- pyo pyr pys pyx rii rio rip rir ris rix riy roi roo rop ror ros rox roy rpi rpo rpp rpr rps rpx rri rrp rrr rrs rsi rso rsp rsr rss rsx rxp rxr rxs ry- ryo ryr rys ryy sii sio sip sir sis six soi soo sop sor sos sox soy spi spo spp spr sps spx spy sr- sri sro srp srr srs srx sry ss- ssi sso ssp ssr sss ssx sxi sxs sy- syi syp syr sys syx xii xio xis xix xoi xoo xop xor xos xox xpo xpp xps xrx xry xsi xsp xss xxi xxo xxp xxx xxy xyp xyr xyy yii yio yip yir yis yoi yoo yop yor yos yox yoy ypo yps yro yrp yrs ysi yso ysp ysr yss ysy yxy yys yyy