YES We show the termination of the TRS R: __(__(X,Y),Z) -> __(X,__(Y,Z)) __(X,nil()) -> X __(nil(),X) -> X U11(tt()) -> tt() U21(tt(),V2) -> U22(isList(activate(V2))) U22(tt()) -> tt() U31(tt()) -> tt() U41(tt(),V2) -> U42(isNeList(activate(V2))) U42(tt()) -> tt() U51(tt(),V2) -> U52(isList(activate(V2))) U52(tt()) -> tt() U61(tt()) -> tt() U71(tt(),P) -> U72(isPal(activate(P))) U72(tt()) -> tt() U81(tt()) -> tt() isList(V) -> U11(isNeList(activate(V))) isList(n__nil()) -> tt() isList(n____(V1,V2)) -> U21(isList(activate(V1)),activate(V2)) isNeList(V) -> U31(isQid(activate(V))) isNeList(n____(V1,V2)) -> U41(isList(activate(V1)),activate(V2)) isNeList(n____(V1,V2)) -> U51(isNeList(activate(V1)),activate(V2)) isNePal(V) -> U61(isQid(activate(V))) isNePal(n____(I,__(P,I))) -> U71(isQid(activate(I)),activate(P)) isPal(V) -> U81(isNePal(activate(V))) isPal(n__nil()) -> tt() isQid(n__a()) -> tt() isQid(n__e()) -> tt() isQid(n__i()) -> tt() isQid(n__o()) -> tt() isQid(n__u()) -> tt() nil() -> n__nil() __(X1,X2) -> n____(X1,X2) a() -> n__a() e() -> n__e() i() -> n__i() o() -> n__o() u() -> n__u() activate(n__nil()) -> nil() activate(n____(X1,X2)) -> __(X1,X2) activate(n__a()) -> a() activate(n__e()) -> e() activate(n__i()) -> i() activate(n__o()) -> o() activate(n__u()) -> u() activate(X) -> X -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: __#(__(X,Y),Z) -> __#(X,__(Y,Z)) p2: __#(__(X,Y),Z) -> __#(Y,Z) p3: U21#(tt(),V2) -> U22#(isList(activate(V2))) p4: U21#(tt(),V2) -> isList#(activate(V2)) p5: U21#(tt(),V2) -> activate#(V2) p6: U41#(tt(),V2) -> U42#(isNeList(activate(V2))) p7: U41#(tt(),V2) -> isNeList#(activate(V2)) p8: U41#(tt(),V2) -> activate#(V2) p9: U51#(tt(),V2) -> U52#(isList(activate(V2))) p10: U51#(tt(),V2) -> isList#(activate(V2)) p11: U51#(tt(),V2) -> activate#(V2) p12: U71#(tt(),P) -> U72#(isPal(activate(P))) p13: U71#(tt(),P) -> isPal#(activate(P)) p14: U71#(tt(),P) -> activate#(P) p15: isList#(V) -> U11#(isNeList(activate(V))) p16: isList#(V) -> isNeList#(activate(V)) p17: isList#(V) -> activate#(V) p18: isList#(n____(V1,V2)) -> U21#(isList(activate(V1)),activate(V2)) p19: isList#(n____(V1,V2)) -> isList#(activate(V1)) p20: isList#(n____(V1,V2)) -> activate#(V1) p21: isList#(n____(V1,V2)) -> activate#(V2) p22: isNeList#(V) -> U31#(isQid(activate(V))) p23: isNeList#(V) -> isQid#(activate(V)) p24: isNeList#(V) -> activate#(V) p25: isNeList#(n____(V1,V2)) -> U41#(isList(activate(V1)),activate(V2)) p26: isNeList#(n____(V1,V2)) -> isList#(activate(V1)) p27: isNeList#(n____(V1,V2)) -> activate#(V1) p28: isNeList#(n____(V1,V2)) -> activate#(V2) p29: isNeList#(n____(V1,V2)) -> U51#(isNeList(activate(V1)),activate(V2)) p30: isNeList#(n____(V1,V2)) -> isNeList#(activate(V1)) p31: isNeList#(n____(V1,V2)) -> activate#(V1) p32: isNeList#(n____(V1,V2)) -> activate#(V2) p33: isNePal#(V) -> U61#(isQid(activate(V))) p34: isNePal#(V) -> isQid#(activate(V)) p35: isNePal#(V) -> activate#(V) p36: isNePal#(n____(I,__(P,I))) -> U71#(isQid(activate(I)),activate(P)) p37: isNePal#(n____(I,__(P,I))) -> isQid#(activate(I)) p38: isNePal#(n____(I,__(P,I))) -> activate#(I) p39: isNePal#(n____(I,__(P,I))) -> activate#(P) p40: isPal#(V) -> U81#(isNePal(activate(V))) p41: isPal#(V) -> isNePal#(activate(V)) p42: isPal#(V) -> activate#(V) p43: activate#(n__nil()) -> nil#() p44: activate#(n____(X1,X2)) -> __#(X1,X2) p45: activate#(n__a()) -> a#() p46: activate#(n__e()) -> e#() p47: activate#(n__i()) -> i#() p48: activate#(n__o()) -> o#() p49: activate#(n__u()) -> u#() and R consists of: r1: __(__(X,Y),Z) -> __(X,__(Y,Z)) r2: __(X,nil()) -> X r3: __(nil(),X) -> X r4: U11(tt()) -> tt() r5: U21(tt(),V2) -> U22(isList(activate(V2))) r6: U22(tt()) -> tt() r7: U31(tt()) -> tt() r8: U41(tt(),V2) -> U42(isNeList(activate(V2))) r9: U42(tt()) -> tt() r10: U51(tt(),V2) -> U52(isList(activate(V2))) r11: U52(tt()) -> tt() r12: U61(tt()) -> tt() r13: U71(tt(),P) -> U72(isPal(activate(P))) r14: U72(tt()) -> tt() r15: U81(tt()) -> tt() r16: isList(V) -> U11(isNeList(activate(V))) r17: isList(n__nil()) -> tt() r18: isList(n____(V1,V2)) -> U21(isList(activate(V1)),activate(V2)) r19: isNeList(V) -> U31(isQid(activate(V))) r20: isNeList(n____(V1,V2)) -> U41(isList(activate(V1)),activate(V2)) r21: isNeList(n____(V1,V2)) -> U51(isNeList(activate(V1)),activate(V2)) r22: isNePal(V) -> U61(isQid(activate(V))) r23: isNePal(n____(I,__(P,I))) -> U71(isQid(activate(I)),activate(P)) r24: isPal(V) -> U81(isNePal(activate(V))) r25: isPal(n__nil()) -> tt() r26: isQid(n__a()) -> tt() r27: isQid(n__e()) -> tt() r28: isQid(n__i()) -> tt() r29: isQid(n__o()) -> tt() r30: isQid(n__u()) -> tt() r31: nil() -> n__nil() r32: __(X1,X2) -> n____(X1,X2) r33: a() -> n__a() r34: e() -> n__e() r35: i() -> n__i() r36: o() -> n__o() r37: u() -> n__u() r38: activate(n__nil()) -> nil() r39: activate(n____(X1,X2)) -> __(X1,X2) r40: activate(n__a()) -> a() r41: activate(n__e()) -> e() r42: activate(n__i()) -> i() r43: activate(n__o()) -> o() r44: activate(n__u()) -> u() r45: activate(X) -> X The estimated dependency graph contains the following SCCs: {p13, p36, p41} {p4, p7, p10, p16, p18, p19, p25, p26, p29, p30} {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: isPal#(V) -> isNePal#(activate(V)) p2: isNePal#(n____(I,__(P,I))) -> U71#(isQid(activate(I)),activate(P)) p3: U71#(tt(),P) -> isPal#(activate(P)) and R consists of: r1: __(__(X,Y),Z) -> __(X,__(Y,Z)) r2: __(X,nil()) -> X r3: __(nil(),X) -> X r4: U11(tt()) -> tt() r5: U21(tt(),V2) -> U22(isList(activate(V2))) r6: U22(tt()) -> tt() r7: U31(tt()) -> tt() r8: U41(tt(),V2) -> U42(isNeList(activate(V2))) r9: U42(tt()) -> tt() r10: U51(tt(),V2) -> U52(isList(activate(V2))) r11: U52(tt()) -> tt() r12: U61(tt()) -> tt() r13: U71(tt(),P) -> U72(isPal(activate(P))) r14: U72(tt()) -> tt() r15: U81(tt()) -> tt() r16: isList(V) -> U11(isNeList(activate(V))) r17: isList(n__nil()) -> tt() r18: isList(n____(V1,V2)) -> U21(isList(activate(V1)),activate(V2)) r19: isNeList(V) -> U31(isQid(activate(V))) r20: isNeList(n____(V1,V2)) -> U41(isList(activate(V1)),activate(V2)) r21: isNeList(n____(V1,V2)) -> U51(isNeList(activate(V1)),activate(V2)) r22: isNePal(V) -> U61(isQid(activate(V))) r23: isNePal(n____(I,__(P,I))) -> U71(isQid(activate(I)),activate(P)) r24: isPal(V) -> U81(isNePal(activate(V))) r25: isPal(n__nil()) -> tt() r26: isQid(n__a()) -> tt() r27: isQid(n__e()) -> tt() r28: isQid(n__i()) -> tt() r29: isQid(n__o()) -> tt() r30: isQid(n__u()) -> tt() r31: nil() -> n__nil() r32: __(X1,X2) -> n____(X1,X2) r33: a() -> n__a() r34: e() -> n__e() r35: i() -> n__i() r36: o() -> n__o() r37: u() -> n__u() r38: activate(n__nil()) -> nil() r39: activate(n____(X1,X2)) -> __(X1,X2) r40: activate(n__a()) -> a() r41: activate(n__e()) -> e() r42: activate(n__i()) -> i() r43: activate(n__o()) -> o() r44: activate(n__u()) -> u() r45: activate(X) -> X The set of usable rules consists of r1, r2, r3, r26, r27, r28, r29, r30, r31, r32, r33, r34, r35, r36, r37, r38, r39, r40, r41, r42, r43, r44, r45 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: isPal#_A(x1) = max{72, x1 + 20} isNePal#_A(x1) = max{19, x1 + 5} activate_A(x1) = max{52, x1 + 14} n_____A(x1,x2) = max{70, x1 + 46, x2} ___A(x1,x2) = max{84, x1 + 59, x2} U71#_A(x1,x2) = max{x1 + 31, x2 + 34} isQid_A(x1) = max{40, x1 + 6} tt_A = 41 nil_A = 53 n__nil_A = 52 a_A = 53 n__a_A = 53 e_A = 51 n__e_A = 36 i_A = 55 n__i_A = 42 o_A = 54 n__o_A = 41 u_A = 53 n__u_A = 40 precedence: nil = n__nil = a > isNePal# = U71# > isPal# = n__i > activate = n__a = o > __ > n____ = n__o > isQid = tt = i = u > e = n__e = n__u partial status: pi(isPal#) = [1] pi(isNePal#) = [1] pi(activate) = [1] pi(n____) = [1, 2] pi(__) = [1, 2] pi(U71#) = [1, 2] pi(isQid) = [1] pi(tt) = [] pi(nil) = [] pi(n__nil) = [] pi(a) = [] pi(n__a) = [] pi(e) = [] pi(n__e) = [] pi(i) = [] pi(n__i) = [] pi(o) = [] pi(n__o) = [] pi(u) = [] pi(n__u) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: isPal#_A(x1) = x1 + 45 isNePal#_A(x1) = x1 + 37 activate_A(x1) = x1 + 7 n_____A(x1,x2) = max{x1 - 8, x2 + 2} ___A(x1,x2) = max{x1 + 57, x2 + 56} U71#_A(x1,x2) = max{60, x2 + 53} isQid_A(x1) = x1 + 127 tt_A = 107 nil_A = 3 n__nil_A = 4 a_A = 3 n__a_A = 4 e_A = 3 n__e_A = 4 i_A = 3 n__i_A = 4 o_A = 3 n__o_A = 4 u_A = 3 n__u_A = 4 precedence: isPal# = isNePal# = activate = n____ = __ = isQid = nil = n__nil = a = n__a = e = n__e = i = n__i = o = n__o > U71# = u > tt = n__u partial status: pi(isPal#) = [1] pi(isNePal#) = [1] pi(activate) = [1] pi(n____) = [2] pi(__) = [] pi(U71#) = [] pi(isQid) = [1] pi(tt) = [] pi(nil) = [] pi(n__nil) = [] pi(a) = [] pi(n__a) = [] pi(e) = [] pi(n__e) = [] pi(i) = [] pi(n__i) = [] pi(o) = [] pi(n__o) = [] pi(u) = [] pi(n__u) = [] The next rules are strictly ordered: p1, p2, p3 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: isNeList#(n____(V1,V2)) -> U51#(isNeList(activate(V1)),activate(V2)) p2: U51#(tt(),V2) -> isList#(activate(V2)) p3: isList#(n____(V1,V2)) -> isList#(activate(V1)) p4: isList#(n____(V1,V2)) -> U21#(isList(activate(V1)),activate(V2)) p5: U21#(tt(),V2) -> isList#(activate(V2)) p6: isList#(V) -> isNeList#(activate(V)) p7: isNeList#(n____(V1,V2)) -> isNeList#(activate(V1)) p8: isNeList#(n____(V1,V2)) -> isList#(activate(V1)) p9: isNeList#(n____(V1,V2)) -> U41#(isList(activate(V1)),activate(V2)) p10: U41#(tt(),V2) -> isNeList#(activate(V2)) and R consists of: r1: __(__(X,Y),Z) -> __(X,__(Y,Z)) r2: __(X,nil()) -> X r3: __(nil(),X) -> X r4: U11(tt()) -> tt() r5: U21(tt(),V2) -> U22(isList(activate(V2))) r6: U22(tt()) -> tt() r7: U31(tt()) -> tt() r8: U41(tt(),V2) -> U42(isNeList(activate(V2))) r9: U42(tt()) -> tt() r10: U51(tt(),V2) -> U52(isList(activate(V2))) r11: U52(tt()) -> tt() r12: U61(tt()) -> tt() r13: U71(tt(),P) -> U72(isPal(activate(P))) r14: U72(tt()) -> tt() r15: U81(tt()) -> tt() r16: isList(V) -> U11(isNeList(activate(V))) r17: isList(n__nil()) -> tt() r18: isList(n____(V1,V2)) -> U21(isList(activate(V1)),activate(V2)) r19: isNeList(V) -> U31(isQid(activate(V))) r20: isNeList(n____(V1,V2)) -> U41(isList(activate(V1)),activate(V2)) r21: isNeList(n____(V1,V2)) -> U51(isNeList(activate(V1)),activate(V2)) r22: isNePal(V) -> U61(isQid(activate(V))) r23: isNePal(n____(I,__(P,I))) -> U71(isQid(activate(I)),activate(P)) r24: isPal(V) -> U81(isNePal(activate(V))) r25: isPal(n__nil()) -> tt() r26: isQid(n__a()) -> tt() r27: isQid(n__e()) -> tt() r28: isQid(n__i()) -> tt() r29: isQid(n__o()) -> tt() r30: isQid(n__u()) -> tt() r31: nil() -> n__nil() r32: __(X1,X2) -> n____(X1,X2) r33: a() -> n__a() r34: e() -> n__e() r35: i() -> n__i() r36: o() -> n__o() r37: u() -> n__u() r38: activate(n__nil()) -> nil() r39: activate(n____(X1,X2)) -> __(X1,X2) r40: activate(n__a()) -> a() r41: activate(n__e()) -> e() r42: activate(n__i()) -> i() r43: activate(n__o()) -> o() r44: activate(n__u()) -> u() r45: activate(X) -> X The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r16, r17, r18, r19, r20, r21, r26, r27, r28, r29, r30, r31, r32, r33, r34, r35, r36, r37, r38, r39, r40, r41, r42, r43, r44, r45 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: isNeList#_A(x1) = max{1, x1} n_____A(x1,x2) = max{x1 + 59, x2} U51#_A(x1,x2) = max{x1 + 36, x2} isNeList_A(x1) = max{22, x1 + 5} activate_A(x1) = max{14, x1} tt_A = 11 isList#_A(x1) = max{14, x1} U21#_A(x1,x2) = max{x1 + 4, x2} isList_A(x1) = max{26, x1 + 23} U41#_A(x1,x2) = max{54, x1 + 16, x2} U22_A(x1) = max{27, x1 - 25} U42_A(x1) = max{12, x1 - 21} U52_A(x1) = max{12, x1 - 45} ___A(x1,x2) = max{x1 + 59, x2} nil_A = 13 U11_A(x1) = max{22, x1 + 3} U21_A(x1,x2) = max{x1 + 16, x2 + 13} U31_A(x1) = max{6, x1 + 1} U41_A(x1,x2) = max{23, x1 - 33, x2 - 15} U51_A(x1,x2) = max{14, x2 + 1} isQid_A(x1) = max{3, x1 + 2} n__a_A = 10 n__e_A = 10 n__i_A = 12 n__o_A = 12 n__u_A = 12 n__nil_A = 0 a_A = 13 e_A = 11 i_A = 13 o_A = 13 u_A = 13 precedence: U52 > isQid > a > n____ = __ > isNeList = U31 = U41 = U51 > U41# > U51# = U21# > isList# > isNeList# > o > activate > nil > isList > U21 > n__a > n__o > n__nil > U11 = i > e > U22 = n__e = n__i > u > tt = U42 = n__u partial status: pi(isNeList#) = [1] pi(n____) = [1, 2] pi(U51#) = [2] pi(isNeList) = [1] pi(activate) = [1] pi(tt) = [] pi(isList#) = [1] pi(U21#) = [1, 2] pi(isList) = [] pi(U41#) = [1, 2] pi(U22) = [] pi(U42) = [] pi(U52) = [] pi(__) = [1, 2] pi(nil) = [] pi(U11) = [] pi(U21) = [2] pi(U31) = [] pi(U41) = [] pi(U51) = [2] pi(isQid) = [1] pi(n__a) = [] pi(n__e) = [] pi(n__i) = [] pi(n__o) = [] pi(n__u) = [] pi(n__nil) = [] pi(a) = [] pi(e) = [] pi(i) = [] pi(o) = [] pi(u) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: isNeList#_A(x1) = max{45, x1 + 6} n_____A(x1,x2) = max{118, x1 + 42, x2 + 110} U51#_A(x1,x2) = x2 + 82 isNeList_A(x1) = 120 activate_A(x1) = max{35, x1 + 2} tt_A = 122 isList#_A(x1) = x1 + 46 U21#_A(x1,x2) = x2 + 108 isList_A(x1) = 135 U41#_A(x1,x2) = max{x1 - 20, x2 + 82} U22_A(x1) = 107 U42_A(x1) = 130 U52_A(x1) = 123 ___A(x1,x2) = max{119, x1 + 43, x2 + 110} nil_A = 36 U11_A(x1) = 134 U21_A(x1,x2) = x2 + 107 U31_A(x1) = 1 U41_A(x1,x2) = 119 U51_A(x1,x2) = max{121, x2 + 1} isQid_A(x1) = max{121, x1 + 91} n__a_A = 123 n__e_A = 35 n__i_A = 31 n__o_A = 35 n__u_A = 32 n__nil_A = 89 a_A = 124 e_A = 36 i_A = 34 o_A = 36 u_A = 32 precedence: __ > n____ = isNeList > U52 = U21 > U41# > isNeList# = U51# > isList# = U21# > nil = U41 > e > U31 > activate = a = i > isList > U11 > U22 = isQid > n__e > U51 > tt > n__nil > n__a = n__u = u > n__o > n__i > o > U42 partial status: pi(isNeList#) = [1] pi(n____) = [1] pi(U51#) = [] pi(isNeList) = [] pi(activate) = [1] pi(tt) = [] pi(isList#) = [] pi(U21#) = [2] pi(isList) = [] pi(U41#) = [2] pi(U22) = [] pi(U42) = [] pi(U52) = [] pi(__) = [2] pi(nil) = [] pi(U11) = [] pi(U21) = [] pi(U31) = [] pi(U41) = [] pi(U51) = [2] pi(isQid) = [] pi(n__a) = [] pi(n__e) = [] pi(n__i) = [] pi(n__o) = [] pi(n__u) = [] pi(n__nil) = [] pi(a) = [] pi(e) = [] pi(i) = [] pi(o) = [] pi(u) = [] The next rules are strictly ordered: p2, p3, p4, p5, p6, p7, p8, p9, p10 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: isNeList#(n____(V1,V2)) -> U51#(isNeList(activate(V1)),activate(V2)) and R consists of: r1: __(__(X,Y),Z) -> __(X,__(Y,Z)) r2: __(X,nil()) -> X r3: __(nil(),X) -> X r4: U11(tt()) -> tt() r5: U21(tt(),V2) -> U22(isList(activate(V2))) r6: U22(tt()) -> tt() r7: U31(tt()) -> tt() r8: U41(tt(),V2) -> U42(isNeList(activate(V2))) r9: U42(tt()) -> tt() r10: U51(tt(),V2) -> U52(isList(activate(V2))) r11: U52(tt()) -> tt() r12: U61(tt()) -> tt() r13: U71(tt(),P) -> U72(isPal(activate(P))) r14: U72(tt()) -> tt() r15: U81(tt()) -> tt() r16: isList(V) -> U11(isNeList(activate(V))) r17: isList(n__nil()) -> tt() r18: isList(n____(V1,V2)) -> U21(isList(activate(V1)),activate(V2)) r19: isNeList(V) -> U31(isQid(activate(V))) r20: isNeList(n____(V1,V2)) -> U41(isList(activate(V1)),activate(V2)) r21: isNeList(n____(V1,V2)) -> U51(isNeList(activate(V1)),activate(V2)) r22: isNePal(V) -> U61(isQid(activate(V))) r23: isNePal(n____(I,__(P,I))) -> U71(isQid(activate(I)),activate(P)) r24: isPal(V) -> U81(isNePal(activate(V))) r25: isPal(n__nil()) -> tt() r26: isQid(n__a()) -> tt() r27: isQid(n__e()) -> tt() r28: isQid(n__i()) -> tt() r29: isQid(n__o()) -> tt() r30: isQid(n__u()) -> tt() r31: nil() -> n__nil() r32: __(X1,X2) -> n____(X1,X2) r33: a() -> n__a() r34: e() -> n__e() r35: i() -> n__i() r36: o() -> n__o() r37: u() -> n__u() r38: activate(n__nil()) -> nil() r39: activate(n____(X1,X2)) -> __(X1,X2) r40: activate(n__a()) -> a() r41: activate(n__e()) -> e() r42: activate(n__i()) -> i() r43: activate(n__o()) -> o() r44: activate(n__u()) -> u() r45: activate(X) -> X The estimated dependency graph contains the following SCCs: (no SCCs) -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: __#(__(X,Y),Z) -> __#(X,__(Y,Z)) p2: __#(__(X,Y),Z) -> __#(Y,Z) and R consists of: r1: __(__(X,Y),Z) -> __(X,__(Y,Z)) r2: __(X,nil()) -> X r3: __(nil(),X) -> X r4: U11(tt()) -> tt() r5: U21(tt(),V2) -> U22(isList(activate(V2))) r6: U22(tt()) -> tt() r7: U31(tt()) -> tt() r8: U41(tt(),V2) -> U42(isNeList(activate(V2))) r9: U42(tt()) -> tt() r10: U51(tt(),V2) -> U52(isList(activate(V2))) r11: U52(tt()) -> tt() r12: U61(tt()) -> tt() r13: U71(tt(),P) -> U72(isPal(activate(P))) r14: U72(tt()) -> tt() r15: U81(tt()) -> tt() r16: isList(V) -> U11(isNeList(activate(V))) r17: isList(n__nil()) -> tt() r18: isList(n____(V1,V2)) -> U21(isList(activate(V1)),activate(V2)) r19: isNeList(V) -> U31(isQid(activate(V))) r20: isNeList(n____(V1,V2)) -> U41(isList(activate(V1)),activate(V2)) r21: isNeList(n____(V1,V2)) -> U51(isNeList(activate(V1)),activate(V2)) r22: isNePal(V) -> U61(isQid(activate(V))) r23: isNePal(n____(I,__(P,I))) -> U71(isQid(activate(I)),activate(P)) r24: isPal(V) -> U81(isNePal(activate(V))) r25: isPal(n__nil()) -> tt() r26: isQid(n__a()) -> tt() r27: isQid(n__e()) -> tt() r28: isQid(n__i()) -> tt() r29: isQid(n__o()) -> tt() r30: isQid(n__u()) -> tt() r31: nil() -> n__nil() r32: __(X1,X2) -> n____(X1,X2) r33: a() -> n__a() r34: e() -> n__e() r35: i() -> n__i() r36: o() -> n__o() r37: u() -> n__u() r38: activate(n__nil()) -> nil() r39: activate(n____(X1,X2)) -> __(X1,X2) r40: activate(n__a()) -> a() r41: activate(n__e()) -> e() r42: activate(n__i()) -> i() r43: activate(n__o()) -> o() r44: activate(n__u()) -> u() r45: activate(X) -> X The set of usable rules consists of r1, r2, r3, r32 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: __#_A(x1,x2) = max{x1 + 4, x2 + 2} ___A(x1,x2) = max{x1 + 2, x2} nil_A = 0 n_____A(x1,x2) = max{x1 + 2, x2} precedence: __# = __ > nil = n____ partial status: pi(__#) = [1] pi(__) = [1, 2] pi(nil) = [] pi(n____) = [1, 2] 2. weighted path order base order: max/plus interpretations on natural numbers: __#_A(x1,x2) = max{0, x1 - 3} ___A(x1,x2) = max{x1 + 5, x2 + 7} nil_A = 0 n_____A(x1,x2) = max{x1 + 6, x2 + 8} precedence: __# = __ = nil = n____ partial status: pi(__#) = [] pi(__) = [2] pi(nil) = [] pi(n____) = [] The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains.