IN = pc0' * pc1' * x
FI = pc0' * pc1  * x * y'

TRl0 = pc0' * pc1' * npc0  * npc1' * (nx ==(x^y)) * (ny==y)
TRl1 = pc0  * pc1' * npc0' * npc1  * (nx == x)    *  ny'

TR = TRl0 + TRl1

POST  = IN + ((IN * TR)?pc0?pc1?x?y)/npc0<-pc0/npc1<-pc1/nx<-x/ny<-y
POST2 = IN + ((POST * TR)?pc0?pc1?x?y)/npc0<-pc0/npc1<-pc1/nx<-x/ny<-y
POST3 = IN + ((POST2 * TR)?pc0?pc1?x?y)/npc0<-pc0/npc1<-pc1/nx<-x/ny<-y

FIU = FI/pc0<-npc0/pc1<-npc1/x<-nx/y<-ny
PRE = FI + (FIU * TR)?npc0?npc1?nx?ny
PREU = PRE/pc0<-npc0/pc1<-npc1/x<-nx/y<-ny
PRE2 = FI + (PREU * TR)?npc0?npc1?nx?ny
PRE2U = PRE2/pc0<-npc0/pc1<-npc1/x<-nx/y<-ny
PRE3 = FI + (PRE2U * TR)?npc0?npc1?nx?ny