YES We show the termination of the TRS R: app(p(),app(s(),x)) -> x app(fact(),|0|()) -> app(s(),|0|()) app(fact(),app(s(),x)) -> app(app(*(),app(s(),x)),app(fact(),app(p(),app(s(),x)))) app(app(*(),|0|()),y) -> |0|() app(app(*(),app(s(),x)),y) -> app(app(+(),app(app(*(),x),y)),y) app(app(+(),x),|0|()) -> x app(app(+(),x),app(s(),y)) -> app(s(),app(app(+(),x),y)) 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(*_0(),y) -> *_1(y) app(*_1(x1),y) -> *_2(x1,y) app(+_0(),y) -> +_1(y) app(+_1(x1),y) -> +_2(x1,y) app(cons_0(),y) -> cons_1(y) app(cons_1(x1),y) -> cons_2(x1,y) app(fact_0(),y) -> fact_1(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(p_0(),y) -> p_1(y) app(s_0(),y) -> s_1(y) p_1(s_1(x)) -> x fact_1(|0|_0()) -> s_1(|0|_0()) fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) *_2(|0|_0(),y) -> |0|_0() *_2(s_1(x),y) -> +_2(*_2(x,y),y) +_2(x,|0|_0()) -> x +_2(x,s_1(y)) -> s_1(+_2(x,y)) 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#(*_1(x1),y) -> *_2#(x1,y) p2: app#(+_1(x1),y) -> +_2#(x1,y) p3: app#(fact_0(),y) -> fact_1#(y) p4: app#(filter_1(x1),y) -> filter_2#(x1,y) p5: app#(filter2_3(x1,x2,x3),y) -> filter2_4#(x1,x2,x3,y) p6: app#(map_1(x1),y) -> map_2#(x1,y) p7: app#(p_0(),y) -> p_1#(y) p8: fact_1#(s_1(x)) -> *_2#(s_1(x),fact_1(p_1(s_1(x)))) p9: fact_1#(s_1(x)) -> fact_1#(p_1(s_1(x))) p10: fact_1#(s_1(x)) -> p_1#(s_1(x)) p11: *_2#(s_1(x),y) -> +_2#(*_2(x,y),y) p12: *_2#(s_1(x),y) -> *_2#(x,y) p13: +_2#(x,s_1(y)) -> +_2#(x,y) p14: map_2#(f,cons_2(x,xs)) -> app#(f,x) p15: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p16: filter_2#(f,cons_2(x,xs)) -> filter2_4#(app(f,x),f,x,xs) p17: filter_2#(f,cons_2(x,xs)) -> app#(f,x) p18: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) p19: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) and R consists of: r1: app(*_0(),y) -> *_1(y) r2: app(*_1(x1),y) -> *_2(x1,y) r3: app(+_0(),y) -> +_1(y) r4: app(+_1(x1),y) -> +_2(x1,y) r5: app(cons_0(),y) -> cons_1(y) r6: app(cons_1(x1),y) -> cons_2(x1,y) r7: app(fact_0(),y) -> fact_1(y) r8: app(filter_0(),y) -> filter_1(y) r9: app(filter_1(x1),y) -> filter_2(x1,y) r10: app(filter2_0(),y) -> filter2_1(y) r11: app(filter2_1(x1),y) -> filter2_2(x1,y) r12: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r13: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r14: app(map_0(),y) -> map_1(y) r15: app(map_1(x1),y) -> map_2(x1,y) r16: app(p_0(),y) -> p_1(y) r17: app(s_0(),y) -> s_1(y) r18: p_1(s_1(x)) -> x r19: fact_1(|0|_0()) -> s_1(|0|_0()) r20: fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) r21: *_2(|0|_0(),y) -> |0|_0() r22: *_2(s_1(x),y) -> +_2(*_2(x,y),y) r23: +_2(x,|0|_0()) -> x r24: +_2(x,s_1(y)) -> s_1(+_2(x,y)) r25: map_2(f,nil_0()) -> nil_0() r26: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r27: filter_2(f,nil_0()) -> nil_0() r28: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r29: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r30: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The estimated dependency graph contains the following SCCs: {p4, p5, p6, p14, p15, p16, p17, p18, p19} {p9} {p12} {p13} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: map_2#(f,cons_2(x,xs)) -> app#(f,x) p2: app#(map_1(x1),y) -> map_2#(x1,y) p3: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p4: app#(filter2_3(x1,x2,x3),y) -> filter2_4#(x1,x2,x3,y) p5: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) p6: filter_2#(f,cons_2(x,xs)) -> app#(f,x) p7: app#(filter_1(x1),y) -> filter_2#(x1,y) 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(*_0(),y) -> *_1(y) r2: app(*_1(x1),y) -> *_2(x1,y) r3: app(+_0(),y) -> +_1(y) r4: app(+_1(x1),y) -> +_2(x1,y) r5: app(cons_0(),y) -> cons_1(y) r6: app(cons_1(x1),y) -> cons_2(x1,y) r7: app(fact_0(),y) -> fact_1(y) r8: app(filter_0(),y) -> filter_1(y) r9: app(filter_1(x1),y) -> filter_2(x1,y) r10: app(filter2_0(),y) -> filter2_1(y) r11: app(filter2_1(x1),y) -> filter2_2(x1,y) r12: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r13: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r14: app(map_0(),y) -> map_1(y) r15: app(map_1(x1),y) -> map_2(x1,y) r16: app(p_0(),y) -> p_1(y) r17: app(s_0(),y) -> s_1(y) r18: p_1(s_1(x)) -> x r19: fact_1(|0|_0()) -> s_1(|0|_0()) r20: fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) r21: *_2(|0|_0(),y) -> |0|_0() r22: *_2(s_1(x),y) -> +_2(*_2(x,y),y) r23: +_2(x,|0|_0()) -> x r24: +_2(x,s_1(y)) -> s_1(+_2(x,y)) r25: map_2(f,nil_0()) -> nil_0() r26: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r27: filter_2(f,nil_0()) -> nil_0() r28: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r29: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r30: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r1, r2, r3, r4, r5, r8, r11, r14, r17, r18, r19, r21, r22, r23, r24, r25 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: map_2#_A(x1,x2) = max{1, x1 - 15, x2 - 7} cons_2_A(x1,x2) = max{x1 + 4, x2 + 6} app#_A(x1,x2) = max{1, x1 - 19, x2 - 3} map_1_A(x1) = max{18, x1 + 4} filter2_3_A(x1,x2,x3) = max{12, x1 - 14, x2 + 4, x3 + 4} filter2_4#_A(x1,x2,x3,x4) = max{1, x2 - 15, x3 - 15, x4 - 3} false_0_A = 33 filter_2#_A(x1,x2) = max{1, x1 - 15, x2 - 7} filter_1_A(x1) = max{12, x1 + 4} app_A(x1,x2) = max{35, x1 - 13, x2 + 17} true_0_A = 33 *_0_A = 12 *_1_A(x1) = x1 + 12 *_2_A(x1,x2) = max{21, x2 - 1} +_0_A = 12 +_1_A(x1) = x1 + 17 +_2_A(x1,x2) = max{21, x1, x2 - 20} cons_0_A = 12 cons_1_A(x1) = x1 + 17 filter_0_A = 12 filter2_1_A(x1) = max{36, x1 + 17} filter2_2_A(x1,x2) = max{24, x1 + 4, x2 + 17} map_0_A = 12 s_0_A = 12 s_1_A(x1) = max{18, x1 - 22} p_1_A(x1) = max{35, x1 + 22} fact_1_A(x1) = max{35, x1 - 78} |0|_0_A = 2 map_2_A(x1,x2) = max{x1 + 39, x2 + 17} nil_0_A = 40 map_2#!_A(x1,x2) = max{2, x2 - 1} cons_2!_A(x1,x2) = max{53, x1 + 13, x2 + 1} app#!_A(x1,x2) = x2 + 7 map_1!_A(x1) = max{3, x1 - 1} filter2_3!_A(x1,x2,x3) = max{53, x1 - 1, x2 - 1, x3 - 1} filter2_4#!_A(x1,x2,x3,x4) = 0 false_0!_A = 55 filter_2#!_A(x1,x2) = 0 filter_1!_A(x1) = max{51, x1 + 49} app!_A(x1,x2) = max{52, x1 - 25, x2 + 50} true_0!_A = 0 *_0!_A = 1 *_1!_A(x1) = max{0, x1 - 1} *_2!_A(x1,x2) = x2 + 21 +_0!_A = 1 +_1!_A(x1) = max{51, x1 - 1} +_2!_A(x1,x2) = 0 cons_0!_A = 53 cons_1!_A(x1) = max{52, x1 - 1} filter_0!_A = 52 filter2_1!_A(x1) = max{22, x1 + 1} filter2_2!_A(x1,x2) = 12 map_0!_A = 2 s_0!_A = 0 s_1!_A(x1) = 0 p_1!_A(x1) = max{52, x1 - 82} fact_1!_A(x1) = max{52, x1 - 41} |0|_0!_A = 0 map_2!_A(x1,x2) = max{49, x2 + 2} nil_0!_A = 41 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: map_2#_A(x1,x2) = max{1, x1 - 2, x2 - 18} cons_2_A(x1,x2) = max{17, x1, x2} app#_A(x1,x2) = max{1, x1 - 2, x2 - 18} map_1_A(x1) = x1 + 1 filter2_3_A(x1,x2,x3) = max{x1 + 1, x2 + 1, x3 + 1} filter2_4#_A(x1,x2,x3,x4) = max{1, x2 - 2, x3 - 18, x4 - 18} false_0_A = 34 filter_2#_A(x1,x2) = max{1, x1 - 2, x2 - 18} filter_1_A(x1) = x1 + 1 app_A(x1,x2) = max{69, x1 - 11, x2 + 16} true_0_A = 34 *_0_A = 1 *_1_A(x1) = 1 *_2_A(x1,x2) = 20 +_0_A = 1 +_1_A(x1) = x1 + 12 +_2_A(x1,x2) = max{17, x1} cons_0_A = 1 cons_1_A(x1) = x1 + 12 filter_0_A = 1 filter2_1_A(x1) = max{10, x1 + 1} filter2_2_A(x1,x2) = x2 + 12 map_0_A = 1 s_0_A = 1 s_1_A(x1) = max{17, x1} p_1_A(x1) = max{33, x1 + 16} fact_1_A(x1) = max{20, x1 - 21} |0|_0_A = 20 map_2_A(x1,x2) = max{69, x1 - 11, x2 + 16} nil_0_A = 70 map_2#!_A(x1,x2) = max{19, x1 + 3, x2 + 2} cons_2!_A(x1,x2) = 2 app#!_A(x1,x2) = max{x1 + 1, x2 - 2} map_1!_A(x1) = x1 + 20 filter2_3!_A(x1,x2,x3) = max{27, x1 - 2, x2 - 1, x3 - 1} filter2_4#!_A(x1,x2,x3,x4) = 0 false_0!_A = 29 filter_2#!_A(x1,x2) = 0 filter_1!_A(x1) = max{21, x1 - 29} app!_A(x1,x2) = x2 + 25 true_0!_A = 0 *_0!_A = 2 *_1!_A(x1) = max{1, x1 - 53} *_2!_A(x1,x2) = max{27, x1 - 52, x2 - 30} +_0!_A = 1 +_1!_A(x1) = max{2, x1 - 1} +_2!_A(x1,x2) = x2 + 24 cons_0!_A = 1 cons_1!_A(x1) = max{0, x1 - 1} filter_0!_A = 1 filter2_1!_A(x1) = 24 filter2_2!_A(x1,x2) = max{26, x1 - 1} map_0!_A = 21 s_0!_A = 0 s_1!_A(x1) = 0 p_1!_A(x1) = 2 fact_1!_A(x1) = max{26, x1 - 34} |0|_0!_A = 0 map_2!_A(x1,x2) = max{21, x1 - 1, x2 - 71} nil_0!_A = 22 partial status: pi(map_2#) = [2] pi(cons_2) = [1, 2] pi(app#) = [2] pi(map_1) = [] pi(filter2_3) = [3] pi(filter2_4#) = [4] pi(false_0) = [] pi(filter_2#) = [2] pi(filter_1) = [1] pi(app) = [1, 2] pi(true_0) = [] pi(*_0) = [] pi(*_1) = [1] pi(*_2) = [1, 2] pi(+_0) = [] pi(+_1) = [1] pi(+_2) = [1, 2] pi(cons_0) = [] pi(cons_1) = [1] pi(filter_0) = [] pi(filter2_1) = [1] pi(filter2_2) = [1] pi(map_0) = [] pi(s_0) = [] pi(s_1) = [1] pi(p_1) = [1] pi(fact_1) = [1] pi(|0|_0) = [] pi(map_2) = [] pi(nil_0) = [] The following rules are removed: p1, p2, p3, p4, p6, p7, p8 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: filter2_4#(false_0(),f,x,xs) -> filter_2#(f,xs) p2: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) and R consists of: r1: app(*_0(),y) -> *_1(y) r2: app(*_1(x1),y) -> *_2(x1,y) r3: app(+_0(),y) -> +_1(y) r4: app(+_1(x1),y) -> +_2(x1,y) r5: app(cons_0(),y) -> cons_1(y) r6: app(cons_1(x1),y) -> cons_2(x1,y) r7: app(fact_0(),y) -> fact_1(y) r8: app(filter_0(),y) -> filter_1(y) r9: app(filter_1(x1),y) -> filter_2(x1,y) r10: app(filter2_0(),y) -> filter2_1(y) r11: app(filter2_1(x1),y) -> filter2_2(x1,y) r12: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r13: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r14: app(map_0(),y) -> map_1(y) r15: app(map_1(x1),y) -> map_2(x1,y) r16: app(p_0(),y) -> p_1(y) r17: app(s_0(),y) -> s_1(y) r18: p_1(s_1(x)) -> x r19: fact_1(|0|_0()) -> s_1(|0|_0()) r20: fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) r21: *_2(|0|_0(),y) -> |0|_0() r22: *_2(s_1(x),y) -> +_2(*_2(x,y),y) r23: +_2(x,|0|_0()) -> x r24: +_2(x,s_1(y)) -> s_1(+_2(x,y)) r25: map_2(f,nil_0()) -> nil_0() r26: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r27: filter_2(f,nil_0()) -> nil_0() r28: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r29: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r30: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The estimated dependency graph contains the following SCCs: (no SCCs) -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: fact_1#(s_1(x)) -> fact_1#(p_1(s_1(x))) and R consists of: r1: app(*_0(),y) -> *_1(y) r2: app(*_1(x1),y) -> *_2(x1,y) r3: app(+_0(),y) -> +_1(y) r4: app(+_1(x1),y) -> +_2(x1,y) r5: app(cons_0(),y) -> cons_1(y) r6: app(cons_1(x1),y) -> cons_2(x1,y) r7: app(fact_0(),y) -> fact_1(y) r8: app(filter_0(),y) -> filter_1(y) r9: app(filter_1(x1),y) -> filter_2(x1,y) r10: app(filter2_0(),y) -> filter2_1(y) r11: app(filter2_1(x1),y) -> filter2_2(x1,y) r12: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r13: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r14: app(map_0(),y) -> map_1(y) r15: app(map_1(x1),y) -> map_2(x1,y) r16: app(p_0(),y) -> p_1(y) r17: app(s_0(),y) -> s_1(y) r18: p_1(s_1(x)) -> x r19: fact_1(|0|_0()) -> s_1(|0|_0()) r20: fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) r21: *_2(|0|_0(),y) -> |0|_0() r22: *_2(s_1(x),y) -> +_2(*_2(x,y),y) r23: +_2(x,|0|_0()) -> x r24: +_2(x,s_1(y)) -> s_1(+_2(x,y)) r25: map_2(f,nil_0()) -> nil_0() r26: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r27: filter_2(f,nil_0()) -> nil_0() r28: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r29: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r30: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r18 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: fact_1#_A(x1) = max{0, x1 - 45} s_1_A(x1) = max{44, x1 + 32} p_1_A(x1) = max{33, x1 - 4} fact_1#!_A(x1) = max{9, x1 - 34} s_1!_A(x1) = max{7, x1 - 86} p_1!_A(x1) = max{8, x1 - 127} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: fact_1#_A(x1) = max{0, x1 - 38} s_1_A(x1) = max{5, x1 + 1} p_1_A(x1) = max{37, x1 - 1} fact_1#!_A(x1) = max{11, x1 - 39} s_1!_A(x1) = max{8, x1 - 39} p_1!_A(x1) = max{10, x1 - 45} partial status: pi(fact_1#) = [1] pi(s_1) = [1] pi(p_1) = [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: *_2#(s_1(x),y) -> *_2#(x,y) and R consists of: r1: app(*_0(),y) -> *_1(y) r2: app(*_1(x1),y) -> *_2(x1,y) r3: app(+_0(),y) -> +_1(y) r4: app(+_1(x1),y) -> +_2(x1,y) r5: app(cons_0(),y) -> cons_1(y) r6: app(cons_1(x1),y) -> cons_2(x1,y) r7: app(fact_0(),y) -> fact_1(y) r8: app(filter_0(),y) -> filter_1(y) r9: app(filter_1(x1),y) -> filter_2(x1,y) r10: app(filter2_0(),y) -> filter2_1(y) r11: app(filter2_1(x1),y) -> filter2_2(x1,y) r12: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r13: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r14: app(map_0(),y) -> map_1(y) r15: app(map_1(x1),y) -> map_2(x1,y) r16: app(p_0(),y) -> p_1(y) r17: app(s_0(),y) -> s_1(y) r18: p_1(s_1(x)) -> x r19: fact_1(|0|_0()) -> s_1(|0|_0()) r20: fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) r21: *_2(|0|_0(),y) -> |0|_0() r22: *_2(s_1(x),y) -> +_2(*_2(x,y),y) r23: +_2(x,|0|_0()) -> x r24: +_2(x,s_1(y)) -> s_1(+_2(x,y)) r25: map_2(f,nil_0()) -> nil_0() r26: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r27: filter_2(f,nil_0()) -> nil_0() r28: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r29: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r30: 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: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: *_2#_A(x1,x2) = 0 s_1_A(x1) = max{5, x1 - 5} *_2#!_A(x1,x2) = max{1, x1 - 22} s_1!_A(x1) = max{2, x1 - 21} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: *_2#_A(x1,x2) = 0 s_1_A(x1) = max{12, x1 - 12} *_2#!_A(x1,x2) = max{11, x1 - 13, x2 - 1} s_1!_A(x1) = max{10, x1 - 101} partial status: pi(*_2#) = [1] pi(s_1) = [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: +_2#(x,s_1(y)) -> +_2#(x,y) and R consists of: r1: app(*_0(),y) -> *_1(y) r2: app(*_1(x1),y) -> *_2(x1,y) r3: app(+_0(),y) -> +_1(y) r4: app(+_1(x1),y) -> +_2(x1,y) r5: app(cons_0(),y) -> cons_1(y) r6: app(cons_1(x1),y) -> cons_2(x1,y) r7: app(fact_0(),y) -> fact_1(y) r8: app(filter_0(),y) -> filter_1(y) r9: app(filter_1(x1),y) -> filter_2(x1,y) r10: app(filter2_0(),y) -> filter2_1(y) r11: app(filter2_1(x1),y) -> filter2_2(x1,y) r12: app(filter2_2(x1,x2),y) -> filter2_3(x1,x2,y) r13: app(filter2_3(x1,x2,x3),y) -> filter2_4(x1,x2,x3,y) r14: app(map_0(),y) -> map_1(y) r15: app(map_1(x1),y) -> map_2(x1,y) r16: app(p_0(),y) -> p_1(y) r17: app(s_0(),y) -> s_1(y) r18: p_1(s_1(x)) -> x r19: fact_1(|0|_0()) -> s_1(|0|_0()) r20: fact_1(s_1(x)) -> *_2(s_1(x),fact_1(p_1(s_1(x)))) r21: *_2(|0|_0(),y) -> |0|_0() r22: *_2(s_1(x),y) -> +_2(*_2(x,y),y) r23: +_2(x,|0|_0()) -> x r24: +_2(x,s_1(y)) -> s_1(+_2(x,y)) r25: map_2(f,nil_0()) -> nil_0() r26: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r27: filter_2(f,nil_0()) -> nil_0() r28: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r29: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r30: 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: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: +_2#_A(x1,x2) = 0 s_1_A(x1) = max{8, x1 - 8} +_2#!_A(x1,x2) = max{1, x2 - 95} s_1!_A(x1) = max{4, x1 - 94} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: +_2#_A(x1,x2) = 0 s_1_A(x1) = max{12, x1 - 12} +_2#!_A(x1,x2) = max{5, x1 - 1, x2 - 13} s_1!_A(x1) = max{4, x1 - 72} partial status: pi(+_2#) = [2] pi(s_1) = [1] The following rules are removed: p1 Then no dependency pair remains.