YES We show the termination of the TRS R: app(app(|:|(),app(app(|:|(),app(app(|:|(),app(app(|:|(),C()),x)),y)),z)),u) -> app(app(|:|(),app(app(|:|(),x),z)),app(app(|:|(),app(app(|:|(),app(app(|:|(),x),y)),z)),u)) app(app(map(),f),nil()) -> nil() app(app(map(),f),app(app(cons(),x),xs)) -> app(app(cons(),app(f,x)),app(app(map(),f),xs)) app(app(filter(),f),nil()) -> nil() app(app(filter(),f),app(app(cons(),x),xs)) -> app(app(app(app(filter2(),app(f,x)),f),x),xs) app(app(app(app(filter2(),true()),f),x),xs) -> app(app(cons(),x),app(app(filter(),f),xs)) app(app(app(app(filter2(),false()),f),x),xs) -> app(app(filter(),f),xs) Instead we prove termination of the uncurried system: app(cons_0(),y) -> cons_1(y) app(cons_1(x1),y) -> cons_2(x1,y) app(filter_0(),y) -> filter_1(y) app(filter_1(x1),y) -> filter_2(x1,y) app(filter2_0(),y) -> filter2_1(y) app(filter2_1(x1),y) -> filter2_2(x1,y) app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) app(map_0(),y) -> map_1(y) app(map_1(x1),y) -> map_2(x1,y) app(|:|_0(),y) -> |:|_1(y) app(|:|_1(x1),y) -> |:|_2(x1,y) |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) map_2(f,nil_0()) -> nil_0() map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) filter_2(f,nil_0()) -> nil_0() filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: app#(filter_1(x1),y) -> filter_2#(x1,y) p2: app#(filter2_3(x1,x2,x3),y) -> filter2_4#(x1,x2,x3,y) p3: app#(map_1(x1),y) -> map_2#(x1,y) p4: app#(|:|_1(x1),y) -> |:|_2#(x1,y) p5: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) p6: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(x,z) p7: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(|:|_2(x,y),z),u) p8: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(x,y),z) p9: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(x,y) p10: map_2#(f,cons_2(x,xs)) -> app#(f,x) p11: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p12: filter_2#(f,cons_2(x,xs)) -> filter2_4#(app(f,x),f,x,xs) p13: filter_2#(f,cons_2(x,xs)) -> app#(f,x) p14: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) p15: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p10, p11, p12, p13, p14, p15} {p5, p6, p7, p8, p9} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: app#(filter_1(x1),y) -> filter_2#(x1,y) p2: filter_2#(f,cons_2(x,xs)) -> app#(f,x) p3: app#(map_1(x1),y) -> map_2#(x1,y) p4: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p5: map_2#(f,cons_2(x,xs)) -> app#(f,x) p6: app#(filter2_3(x1,x2,x3),y) -> filter2_4#(x1,x2,x3,y) p7: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) p8: filter_2#(f,cons_2(x,xs)) -> filter2_4#(app(f,x),f,x,xs) p9: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17, r18, r19 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: app#_A(x1,x2) = max{6, x1 - 4} filter_1_A(x1) = x1 + 12 filter_2#_A(x1,x2) = max{7, x1} cons_2_A(x1,x2) = max{17, x1 - 16, x2} map_1_A(x1) = x1 + 5 map_2#_A(x1,x2) = max{6, x1 - 1} filter2_3_A(x1,x2,x3) = max{x1 - 41, x2 + 11, x3 - 15} filter2_4#_A(x1,x2,x3,x4) = max{7, x2} false_0_A = 46 app_A(x1,x2) = max{39, x1 + 14, x2 + 37} true_0_A = 6 cons_0_A = 27 cons_1_A(x1) = max{40, x1 - 15} filter_0_A = 1 filter_2_A(x1,x2) = max{x1 + 13, x2 + 16} filter2_0_A = 2 filter2_1_A(x1) = max{1, x1 - 15} filter2_2_A(x1,x2) = max{2, x1 - 42, x2 - 1} filter2_4_A(x1,x2,x3,x4) = max{33, x1 - 40, x2 + 13, x3 - 15, x4 + 16} map_0_A = 1 map_2_A(x1,x2) = max{x1 - 2, x2 + 37} |:|_0_A = 1 |:|_1_A(x1) = max{38, x1 - 15} |:|_2_A(x1,x2) = 0 C_0_A = 9 nil_0_A = 4 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: app#_A(x1,x2) = max{0, x1 - 22, x2 - 13} filter_1_A(x1) = max{7, x1 + 6} filter_2#_A(x1,x2) = max{0, x1 - 16, x2 - 13} cons_2_A(x1,x2) = max{12, x1 + 2, x2} map_1_A(x1) = x1 + 5 map_2#_A(x1,x2) = max{0, x1 - 17, x2 - 15} filter2_3_A(x1,x2,x3) = max{16, x1 - 2, x2 + 7, x3 + 13} filter2_4#_A(x1,x2,x3,x4) = max{0, x1 - 24, x2 - 16, x3 - 11, x4 - 13} false_0_A = 15 app_A(x1,x2) = max{23, x1 - 6, x2 + 13} true_0_A = 15 cons_0_A = 5 cons_1_A(x1) = x1 + 13 filter_0_A = 5 filter_2_A(x1,x2) = max{14, x2 + 1} filter2_0_A = 14 filter2_1_A(x1) = x1 + 10 filter2_2_A(x1,x2) = max{x1 + 4, x2 + 13} filter2_4_A(x1,x2,x3,x4) = max{14, x3 + 2, x4 + 1} map_0_A = 5 map_2_A(x1,x2) = max{17, x1 - 1, x2 + 13} |:|_0_A = 5 |:|_1_A(x1) = max{14, x1 + 5} |:|_2_A(x1,x2) = 23 C_0_A = 10 nil_0_A = 18 app#!_A(x1,x2) = max{x1 - 8, x2 + 8} filter_1!_A(x1) = 0 filter_2#!_A(x1,x2) = 0 cons_2!_A(x1,x2) = max{4, x2 - 34} map_1!_A(x1) = max{2, x1 - 17} map_2#!_A(x1,x2) = max{x1 - 4, x2 + 7} filter2_3!_A(x1,x2,x3) = max{36, x1 - 13, x2 - 3, x3 - 1} filter2_4#!_A(x1,x2,x3,x4) = 0 false_0!_A = 1 app!_A(x1,x2) = max{x1 - 15, x2 + 36} true_0!_A = 3 cons_0!_A = 1 cons_1!_A(x1) = max{36, x1 - 1} filter_0!_A = 1 filter_2!_A(x1,x2) = x2 + 35 filter2_0!_A = 1 filter2_1!_A(x1) = max{10, x1 - 1} filter2_2!_A(x1,x2) = max{35, x1 - 13, x2 - 4} filter2_4!_A(x1,x2,x3,x4) = x4 + 35 map_0!_A = 1 map_2!_A(x1,x2) = max{35, x1 - 16, x2 - 20} |:|_0!_A = 1 |:|_1!_A(x1) = max{13, x1 - 1} |:|_2!_A(x1,x2) = max{12, x1 - 11} C_0!_A = 13 nil_0!_A = 34 partial status: pi(app#) = [] pi(filter_1) = [1] pi(filter_2#) = [1] pi(cons_2) = [] pi(map_1) = [1] pi(map_2#) = [] pi(filter2_3) = [] pi(filter2_4#) = [2] pi(false_0) = [] pi(app) = [1] pi(true_0) = [] pi(cons_0) = [] pi(cons_1) = [] pi(filter_0) = [] pi(filter_2) = [1] pi(filter2_0) = [] pi(filter2_1) = [] pi(filter2_2) = [] pi(filter2_4) = [2] pi(map_0) = [] pi(map_2) = [] pi(|:|_0) = [] pi(|:|_1) = [] pi(|:|_2) = [] pi(C_0) = [] pi(nil_0) = [] The following rules are removed: p1, p2, p3, p5, p6 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p2: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) p3: filter_2#(f,cons_2(x,xs)) -> filter2_4#(app(f,x),f,x,xs) p4: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) 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: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) 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: map_2#_A(x1,x2) = max{1, x1 - 1} cons_2_A(x1,x2) = max{0, x1 - 13, x2 - 16} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: map_2#_A(x1,x2) = max{0, x2 - 7} cons_2_A(x1,x2) = max{9, x1 - 20, x2 + 6} map_2#!_A(x1,x2) = max{1, x2 - 7} cons_2!_A(x1,x2) = max{2, x1 - 6, x2 - 33} partial status: pi(map_2#) = [] pi(cons_2) = [] 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: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) p2: filter_2#(f,cons_2(x,xs)) -> filter2_4#(app(f,x),f,x,xs) p3: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r16 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: filter2_4#_A(x1,x2,x3,x4) = 1 false_0_A = 6 filter_2#_A(x1,x2) = 1 cons_2_A(x1,x2) = max{3, x2 - 5} app_A(x1,x2) = max{6, x1 + 5} true_0_A = 6 filter_2_A(x1,x2) = 4 nil_0_A = 1 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: filter2_4#_A(x1,x2,x3,x4) = max{1, x2 - 1, x3 - 30, x4 - 4} false_0_A = 19 filter_2#_A(x1,x2) = max{1, x1 - 1, x2 - 24} cons_2_A(x1,x2) = max{23, x1 - 6, x2 + 20} app_A(x1,x2) = max{x1 - 87, x2 + 19} true_0_A = 19 filter_2_A(x1,x2) = max{23, x1 - 108, x2 + 1} nil_0_A = 24 filter2_4#!_A(x1,x2,x3,x4) = max{x3 + 3, x4 + 11} false_0!_A = 3 filter_2#!_A(x1,x2) = x2 + 10 cons_2!_A(x1,x2) = max{0, x1 - 62, x2 - 24} app!_A(x1,x2) = max{0, x1 - 83, x2 - 25} true_0!_A = 1 filter_2!_A(x1,x2) = 0 nil_0!_A = 0 partial status: pi(filter2_4#) = [] pi(false_0) = [] pi(filter_2#) = [] pi(cons_2) = [] pi(app) = [1] pi(true_0) = [] pi(filter_2) = [] pi(nil_0) = [] The following rules are removed: p1, p2, p3 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) p2: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(x,y) p3: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(x,y),z) p4: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(|:|_2(x,y),z),u) p5: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(x,z) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r13 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: |:|_2#_A(x1,x2) = 1 |:|_2_A(x1,x2) = max{x1 + 13, x2 - 11} C_0_A = 2 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: |:|_2#_A(x1,x2) = max{0, x1 - 38, x2 - 44} |:|_2_A(x1,x2) = max{25, x1 + 6, x2} C_0_A = 0 |:|_2#!_A(x1,x2) = max{5, x1 - 19, x2 - 57} |:|_2!_A(x1,x2) = max{4, x1 - 89, x2 - 95} C_0!_A = 13 partial status: pi(|:|_2#) = [] pi(|:|_2) = [1] pi(C_0) = [] The following rules are removed: p2, p3, p5 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) p2: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(|:|_2(x,y),z),u) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) p2: |:|_2#(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2#(|:|_2(|:|_2(x,y),z),u) and R consists of: r1: app(cons_0(),y) -> cons_1(y) r2: app(cons_1(x1),y) -> cons_2(x1,y) r3: app(filter_0(),y) -> filter_1(y) r4: app(filter_1(x1),y) -> filter_2(x1,y) r5: app(filter2_0(),y) -> filter2_1(y) r6: app(filter2_1(x1),y) -> filter2_2(x1,y) r7: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r8: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r9: app(map_0(),y) -> map_1(y) r10: app(map_1(x1),y) -> map_2(x1,y) r11: app(|:|_0(),y) -> |:|_1(y) r12: app(|:|_1(x1),y) -> |:|_2(x1,y) r13: |:|_2(|:|_2(|:|_2(|:|_2(C_0(),x),y),z),u) -> |:|_2(|:|_2(x,z),|:|_2(|:|_2(|:|_2(x,y),z),u)) r14: map_2(f,nil_0()) -> nil_0() r15: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r16: filter_2(f,nil_0()) -> nil_0() r17: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r18: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r19: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r13 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: |:|_2#_A(x1,x2) = max{x1 + 17, x2 + 15} |:|_2_A(x1,x2) = max{12, x1 + 2, x2} C_0_A = 3 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: |:|_2#_A(x1,x2) = max{0, x1 - 5, x2 - 6} |:|_2_A(x1,x2) = max{7, x1 + 1, x2} C_0_A = 1 |:|_2#!_A(x1,x2) = max{0, x1 - 10, x2 - 11} |:|_2!_A(x1,x2) = 0 C_0!_A = 1 partial status: pi(|:|_2#) = [1] pi(|:|_2) = [1, 2] pi(C_0) = [] The following rules are removed: p1, p2 Then no dependency pair remains.