(VAR V2 L N IL M V1 V X1 X2 X3 X4 X)
(RULES 
active(zeros) -> mark(cons(0,zeros))
active(U11(tt)) -> mark(tt)
active(U21(tt)) -> mark(tt)
active(U31(tt)) -> mark(tt)
active(U41(tt,V2)) -> mark(U42(isNatIList(V2)))
active(U42(tt)) -> mark(tt)
active(U51(tt,V2)) -> mark(U52(isNatList(V2)))
active(U52(tt)) -> mark(tt)
active(U61(tt,V2)) -> mark(U62(isNatIList(V2)))
active(U62(tt)) -> mark(tt)
active(U71(tt,L,N)) -> mark(U72(isNat(N),L))
active(U72(tt,L)) -> mark(s(length(L)))
active(U81(tt)) -> mark(nil)
active(U91(tt,IL,M,N)) -> mark(U92(isNat(M),IL,M,N))
active(U92(tt,IL,M,N)) -> mark(U93(isNat(N),IL,M,N))
active(U93(tt,IL,M,N)) -> mark(cons(N,take(M,IL)))
active(isNat(0)) -> mark(tt)
active(isNat(length(V1))) -> mark(U11(isNatList(V1)))
active(isNat(s(V1))) -> mark(U21(isNat(V1)))
active(isNatIList(V)) -> mark(U31(isNatList(V)))
active(isNatIList(zeros)) -> mark(tt)
active(isNatIList(cons(V1,V2))) -> mark(U41(isNat(V1),V2))
active(isNatList(nil)) -> mark(tt)
active(isNatList(cons(V1,V2))) -> mark(U51(isNat(V1),V2))
active(isNatList(take(V1,V2))) -> mark(U61(isNat(V1),V2))
active(length(nil)) -> mark(0)
active(length(cons(N,L))) -> mark(U71(isNatList(L),L,N))
active(take(0,IL)) -> mark(U81(isNatIList(IL)))
active(take(s(M),cons(N,IL))) -> mark(U91(isNatIList(IL),IL,M,N))
mark(zeros) -> active(zeros)
mark(cons(X1,X2)) -> active(cons(mark(X1),X2))
mark(0) -> active(0)
mark(U11(X)) -> active(U11(mark(X)))
mark(tt) -> active(tt)
mark(U21(X)) -> active(U21(mark(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(isNatIList(X)) -> active(isNatIList(X))
mark(U51(X1,X2)) -> active(U51(mark(X1),X2))
mark(U52(X)) -> active(U52(mark(X)))
mark(isNatList(X)) -> active(isNatList(X))
mark(U61(X1,X2)) -> active(U61(mark(X1),X2))
mark(U62(X)) -> active(U62(mark(X)))
mark(U71(X1,X2,X3)) -> active(U71(mark(X1),X2,X3))
mark(U72(X1,X2)) -> active(U72(mark(X1),X2))
mark(isNat(X)) -> active(isNat(X))
mark(s(X)) -> active(s(mark(X)))
mark(length(X)) -> active(length(mark(X)))
mark(U81(X)) -> active(U81(mark(X)))
mark(nil) -> active(nil)
mark(U91(X1,X2,X3,X4)) -> active(U91(mark(X1),X2,X3,X4))
mark(U92(X1,X2,X3,X4)) -> active(U92(mark(X1),X2,X3,X4))
mark(U93(X1,X2,X3,X4)) -> active(U93(mark(X1),X2,X3,X4))
mark(take(X1,X2)) -> active(take(mark(X1),mark(X2)))
cons(mark(X1),X2) -> cons(X1,X2)
cons(X1,mark(X2)) -> cons(X1,X2)
cons(active(X1),X2) -> cons(X1,X2)
cons(X1,active(X2)) -> cons(X1,X2)
U11(mark(X)) -> U11(X)
U11(active(X)) -> U11(X)
U21(mark(X)) -> U21(X)
U21(active(X)) -> U21(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)
isNatIList(mark(X)) -> isNatIList(X)
isNatIList(active(X)) -> isNatIList(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)
isNatList(mark(X)) -> isNatList(X)
isNatList(active(X)) -> isNatList(X)
U61(mark(X1),X2) -> U61(X1,X2)
U61(X1,mark(X2)) -> U61(X1,X2)
U61(active(X1),X2) -> U61(X1,X2)
U61(X1,active(X2)) -> U61(X1,X2)
U62(mark(X)) -> U62(X)
U62(active(X)) -> U62(X)
U71(mark(X1),X2,X3) -> U71(X1,X2,X3)
U71(X1,mark(X2),X3) -> U71(X1,X2,X3)
U71(X1,X2,mark(X3)) -> U71(X1,X2,X3)
U71(active(X1),X2,X3) -> U71(X1,X2,X3)
U71(X1,active(X2),X3) -> U71(X1,X2,X3)
U71(X1,X2,active(X3)) -> U71(X1,X2,X3)
U72(mark(X1),X2) -> U72(X1,X2)
U72(X1,mark(X2)) -> U72(X1,X2)
U72(active(X1),X2) -> U72(X1,X2)
U72(X1,active(X2)) -> U72(X1,X2)
isNat(mark(X)) -> isNat(X)
isNat(active(X)) -> isNat(X)
s(mark(X)) -> s(X)
s(active(X)) -> s(X)
length(mark(X)) -> length(X)
length(active(X)) -> length(X)
U81(mark(X)) -> U81(X)
U81(active(X)) -> U81(X)
U91(mark(X1),X2,X3,X4) -> U91(X1,X2,X3,X4)
U91(X1,mark(X2),X3,X4) -> U91(X1,X2,X3,X4)
U91(X1,X2,mark(X3),X4) -> U91(X1,X2,X3,X4)
U91(X1,X2,X3,mark(X4)) -> U91(X1,X2,X3,X4)
U91(active(X1),X2,X3,X4) -> U91(X1,X2,X3,X4)
U91(X1,active(X2),X3,X4) -> U91(X1,X2,X3,X4)
U91(X1,X2,active(X3),X4) -> U91(X1,X2,X3,X4)
U91(X1,X2,X3,active(X4)) -> U91(X1,X2,X3,X4)
U92(mark(X1),X2,X3,X4) -> U92(X1,X2,X3,X4)
U92(X1,mark(X2),X3,X4) -> U92(X1,X2,X3,X4)
U92(X1,X2,mark(X3),X4) -> U92(X1,X2,X3,X4)
U92(X1,X2,X3,mark(X4)) -> U92(X1,X2,X3,X4)
U92(active(X1),X2,X3,X4) -> U92(X1,X2,X3,X4)
U92(X1,active(X2),X3,X4) -> U92(X1,X2,X3,X4)
U92(X1,X2,active(X3),X4) -> U92(X1,X2,X3,X4)
U92(X1,X2,X3,active(X4)) -> U92(X1,X2,X3,X4)
U93(mark(X1),X2,X3,X4) -> U93(X1,X2,X3,X4)
U93(X1,mark(X2),X3,X4) -> U93(X1,X2,X3,X4)
U93(X1,X2,mark(X3),X4) -> U93(X1,X2,X3,X4)
U93(X1,X2,X3,mark(X4)) -> U93(X1,X2,X3,X4)
U93(active(X1),X2,X3,X4) -> U93(X1,X2,X3,X4)
U93(X1,active(X2),X3,X4) -> U93(X1,X2,X3,X4)
U93(X1,X2,active(X3),X4) -> U93(X1,X2,X3,X4)
U93(X1,X2,X3,active(X4)) -> U93(X1,X2,X3,X4)
take(mark(X1),X2) -> take(X1,X2)
take(X1,mark(X2)) -> take(X1,X2)
take(active(X1),X2) -> take(X1,X2)
take(X1,active(X2)) -> take(X1,X2)
)