(VAR X Y Z V2 P V V1 I X1 X2)
(RULES 
active(__(__(X,Y),Z)) -> mark(__(X,__(Y,Z)))
active(__(X,nil)) -> mark(X)
active(__(nil,X)) -> mark(X)
active(U11(tt)) -> mark(tt)
active(U21(tt,V2)) -> mark(U22(isList(V2)))
active(U22(tt)) -> mark(tt)
active(U31(tt)) -> mark(tt)
active(U41(tt,V2)) -> mark(U42(isNeList(V2)))
active(U42(tt)) -> mark(tt)
active(U51(tt,V2)) -> mark(U52(isList(V2)))
active(U52(tt)) -> mark(tt)
active(U61(tt)) -> mark(tt)
active(U71(tt,P)) -> mark(U72(isPal(P)))
active(U72(tt)) -> mark(tt)
active(U81(tt)) -> mark(tt)
active(isList(V)) -> mark(U11(isNeList(V)))
active(isList(nil)) -> mark(tt)
active(isList(__(V1,V2))) -> mark(U21(isList(V1),V2))
active(isNeList(V)) -> mark(U31(isQid(V)))
active(isNeList(__(V1,V2))) -> mark(U41(isList(V1),V2))
active(isNeList(__(V1,V2))) -> mark(U51(isNeList(V1),V2))
active(isNePal(V)) -> mark(U61(isQid(V)))
active(isNePal(__(I,__(P,I)))) -> mark(U71(isQid(I),P))
active(isPal(V)) -> mark(U81(isNePal(V)))
active(isPal(nil)) -> mark(tt)
active(isQid(a)) -> mark(tt)
active(isQid(e)) -> mark(tt)
active(isQid(i)) -> mark(tt)
active(isQid(o)) -> mark(tt)
active(isQid(u)) -> mark(tt)
mark(__(X1,X2)) -> active(__(mark(X1),mark(X2)))
mark(nil) -> active(nil)
mark(U11(X)) -> active(U11(mark(X)))
mark(tt) -> active(tt)
mark(U21(X1,X2)) -> active(U21(mark(X1),X2))
mark(U22(X)) -> active(U22(mark(X)))
mark(isList(X)) -> active(isList(X))
mark(U31(X)) -> active(U31(mark(X)))
mark(U41(X1,X2)) -> active(U41(mark(X1),X2))
mark(U42(X)) -> active(U42(mark(X)))
mark(isNeList(X)) -> active(isNeList(X))
mark(U51(X1,X2)) -> active(U51(mark(X1),X2))
mark(U52(X)) -> active(U52(mark(X)))
mark(U61(X)) -> active(U61(mark(X)))
mark(U71(X1,X2)) -> active(U71(mark(X1),X2))
mark(U72(X)) -> active(U72(mark(X)))
mark(isPal(X)) -> active(isPal(X))
mark(U81(X)) -> active(U81(mark(X)))
mark(isQid(X)) -> active(isQid(X))
mark(isNePal(X)) -> active(isNePal(X))
mark(a) -> active(a)
mark(e) -> active(e)
mark(i) -> active(i)
mark(o) -> active(o)
mark(u) -> active(u)
__(mark(X1),X2) -> __(X1,X2)
__(X1,mark(X2)) -> __(X1,X2)
__(active(X1),X2) -> __(X1,X2)
__(X1,active(X2)) -> __(X1,X2)
U11(mark(X)) -> U11(X)
U11(active(X)) -> U11(X)
U21(mark(X1),X2) -> U21(X1,X2)
U21(X1,mark(X2)) -> U21(X1,X2)
U21(active(X1),X2) -> U21(X1,X2)
U21(X1,active(X2)) -> U21(X1,X2)
U22(mark(X)) -> U22(X)
U22(active(X)) -> U22(X)
isList(mark(X)) -> isList(X)
isList(active(X)) -> isList(X)
U31(mark(X)) -> U31(X)
U31(active(X)) -> U31(X)
U41(mark(X1),X2) -> U41(X1,X2)
U41(X1,mark(X2)) -> U41(X1,X2)
U41(active(X1),X2) -> U41(X1,X2)
U41(X1,active(X2)) -> U41(X1,X2)
U42(mark(X)) -> U42(X)
U42(active(X)) -> U42(X)
isNeList(mark(X)) -> isNeList(X)
isNeList(active(X)) -> isNeList(X)
U51(mark(X1),X2) -> U51(X1,X2)
U51(X1,mark(X2)) -> U51(X1,X2)
U51(active(X1),X2) -> U51(X1,X2)
U51(X1,active(X2)) -> U51(X1,X2)
U52(mark(X)) -> U52(X)
U52(active(X)) -> U52(X)
U61(mark(X)) -> U61(X)
U61(active(X)) -> U61(X)
U71(mark(X1),X2) -> U71(X1,X2)
U71(X1,mark(X2)) -> U71(X1,X2)
U71(active(X1),X2) -> U71(X1,X2)
U71(X1,active(X2)) -> U71(X1,X2)
U72(mark(X)) -> U72(X)
U72(active(X)) -> U72(X)
isPal(mark(X)) -> isPal(X)
isPal(active(X)) -> isPal(X)
U81(mark(X)) -> U81(X)
U81(active(X)) -> U81(X)
isQid(mark(X)) -> isQid(X)
isQid(active(X)) -> isQid(X)
isNePal(mark(X)) -> isNePal(X)
isNePal(active(X)) -> isNePal(X)
)