i-v iii iio iip iit io- ioi ioo iop iot iov ipi ipo ipp ipt ipv iti ito itp itt itv ivi ivo ivp ivt ivv o-i oii oio oip oit oiv oo- ooi ooo oop oot oov op- opi opo opp opt opv ot- oti oto otp ott otv ov- ovi ovo ovp ovv p-p pii pio pip pit piv poi poo pop pot pov ppi ppo ppp ppt ppv pt- pti pto ptp ptt ptv pvi pvo pvp pvt pvv tii tio tip tit tiv to- toi too top tot tov tpi tpo tpp tpt tpv tti tto ttp ttt ttv tvi tvo tvp tvt vi- vii vio vip vit viv voi voo vop vot vov vpi vpo vpp vpt vti vto vtt vtv vvi vvo vvt vvv