YES We show the termination of the TRS R: ap(ap(map(),f),xs) -> ap(ap(ap(if(),ap(isEmpty(),xs)),f),xs) ap(ap(ap(if(),true()),f),xs) -> nil() ap(ap(ap(if(),false()),f),xs) -> ap(ap(cons(),ap(f,ap(last(),xs))),ap(ap(map(),f),ap(dropLast(),xs))) ap(isEmpty(),nil()) -> true() ap(isEmpty(),ap(ap(cons(),x),xs)) -> false() ap(last(),ap(ap(cons(),x),nil())) -> x ap(last(),ap(ap(cons(),x),ap(ap(cons(),y),ys))) -> ap(last(),ap(ap(cons(),y),ys)) ap(dropLast(),nil()) -> nil() ap(dropLast(),ap(ap(cons(),x),nil())) -> nil() ap(dropLast(),ap(ap(cons(),x),ap(ap(cons(),y),ys))) -> ap(ap(cons(),x),ap(dropLast(),ap(ap(cons(),y),ys))) Instead we prove termination of the uncurried system: ap(cons_0(),y) -> cons_1(y) ap(cons_1(x1),y) -> cons_2(x1,y) ap(dropLast_0(),y) -> dropLast_1(y) ap(if_0(),y) -> if_1(y) ap(if_1(x1),y) -> if_2(x1,y) ap(if_2(x1,x2),y) -> if_3(x1,x2,y) ap(isEmpty_0(),y) -> isEmpty_1(y) ap(last_0(),y) -> last_1(y) ap(map_0(),y) -> map_1(y) ap(map_1(x1),y) -> map_2(x1,y) map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) if_3(true_0(),f,xs) -> nil_0() if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) isEmpty_1(nil_0()) -> true_0() isEmpty_1(cons_2(x,xs)) -> false_0() last_1(cons_2(x,nil_0())) -> x last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) dropLast_1(nil_0()) -> nil_0() dropLast_1(cons_2(x,nil_0())) -> nil_0() dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: ap#(dropLast_0(),y) -> dropLast_1#(y) p2: ap#(if_2(x1,x2),y) -> if_3#(x1,x2,y) p3: ap#(isEmpty_0(),y) -> isEmpty_1#(y) p4: ap#(last_0(),y) -> last_1#(y) p5: ap#(map_1(x1),y) -> map_2#(x1,y) p6: map_2#(f,xs) -> if_3#(isEmpty_1(xs),f,xs) p7: map_2#(f,xs) -> isEmpty_1#(xs) p8: if_3#(false_0(),f,xs) -> ap#(f,last_1(xs)) p9: if_3#(false_0(),f,xs) -> last_1#(xs) p10: if_3#(false_0(),f,xs) -> map_2#(f,dropLast_1(xs)) p11: if_3#(false_0(),f,xs) -> dropLast_1#(xs) p12: last_1#(cons_2(x,cons_2(y,ys))) -> last_1#(cons_2(y,ys)) p13: dropLast_1#(cons_2(x,cons_2(y,ys))) -> dropLast_1#(cons_2(y,ys)) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The estimated dependency graph contains the following SCCs: {p2, p5, p6, p8, p10} {p13} {p12} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: if_3#(false_0(),f,xs) -> ap#(f,last_1(xs)) p2: ap#(map_1(x1),y) -> map_2#(x1,y) p3: map_2#(f,xs) -> if_3#(isEmpty_1(xs),f,xs) p4: if_3#(false_0(),f,xs) -> map_2#(f,dropLast_1(xs)) p5: ap#(if_2(x1,x2),y) -> if_3#(x1,x2,y) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The set of usable rules consists of r7, r14, r15 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: if_3#_A(x1,x2,x3) = 1 false_0_A = 0 ap#_A(x1,x2) = 1 last_1_A(x1) = max{5, x1 - 6} map_1_A(x1) = max{3, x1 - 26} map_2#_A(x1,x2) = 1 isEmpty_1_A(x1) = max{2, x1 - 15} dropLast_1_A(x1) = max{0, x1 - 6} if_2_A(x1,x2) = max{2, x1 - 26, x2 - 26} ap_A(x1,x2) = max{4, x1 - 15, x2 - 9} isEmpty_0_A = 1 nil_0_A = 0 true_0_A = 0 cons_2_A(x1,x2) = max{0, x2 - 9} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: if_3#_A(x1,x2,x3) = max{1, x1 - 8, x2 - 137} false_0_A = 1 ap#_A(x1,x2) = max{1, x1 - 137} last_1_A(x1) = max{93, x1 - 1} map_1_A(x1) = max{136, x1 + 130} map_2#_A(x1,x2) = max{1, x1 - 137} isEmpty_1_A(x1) = 1 dropLast_1_A(x1) = max{21, x1 - 23} if_2_A(x1,x2) = max{130, x1 + 129, x2 + 129} ap_A(x1,x2) = max{57, x1 - 199, x2 - 36} isEmpty_0_A = 165 nil_0_A = 22 true_0_A = 1 cons_2_A(x1,x2) = max{22, x1 - 35, x2 - 35} if_3#!_A(x1,x2,x3) = max{4, x1 - 2, x2 - 130} false_0!_A = 3 ap#!_A(x1,x2) = max{4, x1 - 131} last_1!_A(x1) = max{8, x1 - 152} map_1!_A(x1) = max{5, x1 - 129} map_2#!_A(x1,x2) = max{4, x1 - 130} isEmpty_1!_A(x1) = max{5, x1 - 133} dropLast_1!_A(x1) = max{2, x1 - 111} if_2!_A(x1,x2) = max{5, x1 - 1, x2 - 33} ap!_A(x1,x2) = max{7, x1 - 164, x2 - 128} isEmpty_0!_A = 1 nil_0!_A = 1 true_0!_A = 0 cons_2!_A(x1,x2) = max{4, x1 - 90, x2 - 129} partial status: pi(if_3#) = [] pi(false_0) = [] pi(ap#) = [] pi(last_1) = [] pi(map_1) = [] pi(map_2#) = [] pi(isEmpty_1) = [] pi(dropLast_1) = [] pi(if_2) = [] pi(ap) = [] pi(isEmpty_0) = [] pi(nil_0) = [] pi(true_0) = [] pi(cons_2) = [] The following rules are removed: p2 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: if_3#(false_0(),f,xs) -> ap#(f,last_1(xs)) p2: map_2#(f,xs) -> if_3#(isEmpty_1(xs),f,xs) p3: if_3#(false_0(),f,xs) -> map_2#(f,dropLast_1(xs)) p4: ap#(if_2(x1,x2),y) -> if_3#(x1,x2,y) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: if_3#(false_0(),f,xs) -> ap#(f,last_1(xs)) p2: ap#(if_2(x1,x2),y) -> if_3#(x1,x2,y) p3: if_3#(false_0(),f,xs) -> map_2#(f,dropLast_1(xs)) p4: map_2#(f,xs) -> if_3#(isEmpty_1(xs),f,xs) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The set of usable rules consists of r7, r14, r15, r16, r17, r18, r19, r20 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: if_3#_A(x1,x2,x3) = 0 false_0_A = 8 ap#_A(x1,x2) = 0 last_1_A(x1) = max{51, x1 + 35} if_2_A(x1,x2) = max{18, x1 - 106, x2 - 15} map_2#_A(x1,x2) = 0 dropLast_1_A(x1) = max{27, x1 + 11} isEmpty_1_A(x1) = max{15, x1 - 53} ap_A(x1,x2) = max{16, x1 - 53, x2 - 52} isEmpty_0_A = 1 nil_0_A = 29 true_0_A = 0 cons_2_A(x1,x2) = max{17, x1 - 21, x2 + 9} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: if_3#_A(x1,x2,x3) = max{0, x1 - 9, x2 - 29, x3 - 13} false_0_A = 0 ap#_A(x1,x2) = max{0, x1 - 29, x2 - 9} last_1_A(x1) = max{1, x1 - 4} if_2_A(x1,x2) = max{x1 + 20, x2 + 2} map_2#_A(x1,x2) = max{0, x1 - 29, x2 - 13} dropLast_1_A(x1) = max{12, x1} isEmpty_1_A(x1) = max{0, x1 - 34} ap_A(x1,x2) = max{0, x1 - 45, x2 - 19} isEmpty_0_A = 42 nil_0_A = 27 true_0_A = 0 cons_2_A(x1,x2) = max{26, x1 + 17, x2 + 5} if_3#!_A(x1,x2,x3) = max{16, x1 - 3, x2 - 2, x3 + 2} false_0!_A = 15 ap#!_A(x1,x2) = max{x1 - 3, x2 + 3} last_1!_A(x1) = max{16, x1 - 42} if_2!_A(x1,x2) = max{19, x1 - 23} map_2#!_A(x1,x2) = max{16, x1 - 2, x2 + 2} dropLast_1!_A(x1) = max{21, x1 - 33} isEmpty_1!_A(x1) = max{16, x1 - 56} ap!_A(x1,x2) = max{18, x1 - 43, x2 - 44} isEmpty_0!_A = 1 nil_0!_A = 1 true_0!_A = 0 cons_2!_A(x1,x2) = max{15, x1 - 21, x2 - 34} partial status: pi(if_3#) = [] pi(false_0) = [] pi(ap#) = [] pi(last_1) = [] pi(if_2) = [] pi(map_2#) = [] pi(dropLast_1) = [] pi(isEmpty_1) = [] pi(ap) = [] pi(isEmpty_0) = [] pi(nil_0) = [] pi(true_0) = [] pi(cons_2) = [2] The following rules are removed: p1, p2 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: if_3#(false_0(),f,xs) -> map_2#(f,dropLast_1(xs)) p2: map_2#(f,xs) -> if_3#(isEmpty_1(xs),f,xs) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: if_3#(false_0(),f,xs) -> map_2#(f,dropLast_1(xs)) p2: map_2#(f,xs) -> if_3#(isEmpty_1(xs),f,xs) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The set of usable rules consists of r3, r14, r15, r18, r19, r20 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: if_3#_A(x1,x2,x3) = max{x1 - 2, x3 + 37} false_0_A = 51 map_2#_A(x1,x2) = max{49, x2 + 41} dropLast_1_A(x1) = max{7, x1 - 4} isEmpty_1_A(x1) = x1 + 40 ap_A(x1,x2) = x2 + 35 dropLast_0_A = 37 nil_0_A = 6 true_0_A = 2 cons_2_A(x1,x2) = x2 + 11 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: if_3#_A(x1,x2,x3) = max{x1 - 33, x2 + 5} false_0_A = 34 map_2#_A(x1,x2) = max{x1 + 5, x2 - 9} dropLast_1_A(x1) = 14 isEmpty_1_A(x1) = x1 + 24 ap_A(x1,x2) = max{14, x1 - 42, x2 - 22} dropLast_0_A = 19 nil_0_A = 13 true_0_A = 34 cons_2_A(x1,x2) = 13 if_3#!_A(x1,x2,x3) = max{0, x1 - 26} false_0!_A = 5 map_2#!_A(x1,x2) = max{7, x2 - 10} dropLast_1!_A(x1) = x1 + 24 isEmpty_1!_A(x1) = x1 + 37 ap!_A(x1,x2) = max{3, x1 - 18, x2 - 26} dropLast_0!_A = 1 nil_0!_A = 0 true_0!_A = 5 cons_2!_A(x1,x2) = 0 partial status: pi(if_3#) = [] pi(false_0) = [] pi(map_2#) = [] pi(dropLast_1) = [] pi(isEmpty_1) = [1] pi(ap) = [2] pi(dropLast_0) = [] pi(nil_0) = [] pi(true_0) = [] pi(cons_2) = [] The following rules are removed: p1, p2 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: dropLast_1#(cons_2(x,cons_2(y,ys))) -> dropLast_1#(cons_2(y,ys)) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The set of usable rules consists of r12, r18 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: dropLast_1#_A(x1) = max{13, x1 - 1} cons_2_A(x1,x2) = max{13, x2 + 4} if_3_A(x1,x2,x3) = max{11, x1 - 57, x2 - 17, x3 - 1} true_0_A = 0 nil_0_A = 1 dropLast_1_A(x1) = max{10, x1 - 18} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: dropLast_1#_A(x1) = 0 cons_2_A(x1,x2) = max{x1 - 9, x2 + 10} if_3_A(x1,x2,x3) = max{11, x1 - 42, x2 - 93, x3 - 33} true_0_A = 2 nil_0_A = 10 dropLast_1_A(x1) = 48 dropLast_1#!_A(x1) = max{17, x1 - 4} cons_2!_A(x1,x2) = max{x1 + 68, x2 + 6} if_3!_A(x1,x2,x3) = max{x1 - 3, x2 - 14, x3 + 46} true_0!_A = 0 nil_0!_A = 70 dropLast_1!_A(x1) = 69 partial status: pi(dropLast_1#) = [] pi(cons_2) = [] pi(if_3) = [] pi(true_0) = [] pi(nil_0) = [] pi(dropLast_1) = [] The following rules are removed: p1 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: last_1#(cons_2(x,cons_2(y,ys))) -> last_1#(cons_2(y,ys)) and R consists of: r1: ap(cons_0(),y) -> cons_1(y) r2: ap(cons_1(x1),y) -> cons_2(x1,y) r3: ap(dropLast_0(),y) -> dropLast_1(y) r4: ap(if_0(),y) -> if_1(y) r5: ap(if_1(x1),y) -> if_2(x1,y) r6: ap(if_2(x1,x2),y) -> if_3(x1,x2,y) r7: ap(isEmpty_0(),y) -> isEmpty_1(y) r8: ap(last_0(),y) -> last_1(y) r9: ap(map_0(),y) -> map_1(y) r10: ap(map_1(x1),y) -> map_2(x1,y) r11: map_2(f,xs) -> if_3(isEmpty_1(xs),f,xs) r12: if_3(true_0(),f,xs) -> nil_0() r13: if_3(false_0(),f,xs) -> cons_2(ap(f,last_1(xs)),map_2(f,dropLast_1(xs))) r14: isEmpty_1(nil_0()) -> true_0() r15: isEmpty_1(cons_2(x,xs)) -> false_0() r16: last_1(cons_2(x,nil_0())) -> x r17: last_1(cons_2(x,cons_2(y,ys))) -> last_1(cons_2(y,ys)) r18: dropLast_1(nil_0()) -> nil_0() r19: dropLast_1(cons_2(x,nil_0())) -> nil_0() r20: dropLast_1(cons_2(x,cons_2(y,ys))) -> cons_2(x,dropLast_1(cons_2(y,ys))) The set of usable rules consists of (no rules) Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: last_1#_A(x1) = max{12, x1} cons_2_A(x1,x2) = max{x1 + 12, x2} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: last_1#_A(x1) = 0 cons_2_A(x1,x2) = max{0, x1 - 9, x2 - 9} last_1#!_A(x1) = x1 + 20 cons_2!_A(x1,x2) = max{x1 - 14, x2 + 28} partial status: pi(last_1#) = [1] pi(cons_2) = [2] The following rules are removed: p1 Then no dependency pair remains.