YES We show the termination of the TRS R: app(app(times(),x),|0|()) -> |0|() app(app(times(),x),app(s(),y)) -> app(app(plus(),app(app(times(),x),y)),x) app(app(plus(),x),|0|()) -> x app(app(plus(),|0|()),x) -> x app(app(plus(),x),app(s(),y)) -> app(s(),app(app(plus(),x),y)) app(app(plus(),app(s(),x)),y) -> app(s(),app(app(plus(),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(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(plus_0(),y) -> plus_1(y) app(plus_1(x1),y) -> plus_2(x1,y) app(s_0(),y) -> s_1(y) app(times_0(),y) -> times_1(y) app(times_1(x1),y) -> times_2(x1,y) times_2(x,|0|_0()) -> |0|_0() times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) plus_2(x,|0|_0()) -> x plus_2(|0|_0(),x) -> x plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) plus_2(s_1(x),y) -> s_1(plus_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#(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#(plus_1(x1),y) -> plus_2#(x1,y) p5: app#(times_1(x1),y) -> times_2#(x1,y) p6: times_2#(x,s_1(y)) -> plus_2#(times_2(x,y),x) p7: times_2#(x,s_1(y)) -> times_2#(x,y) p8: plus_2#(x,s_1(y)) -> plus_2#(x,y) p9: plus_2#(s_1(x),y) -> plus_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(plus_0(),y) -> plus_1(y) r12: app(plus_1(x1),y) -> plus_2(x1,y) r13: app(s_0(),y) -> s_1(y) r14: app(times_0(),y) -> times_1(y) r15: app(times_1(x1),y) -> times_2(x1,y) r16: times_2(x,|0|_0()) -> |0|_0() r17: times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) r18: plus_2(x,|0|_0()) -> x r19: plus_2(|0|_0(),x) -> x r20: plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) r21: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) r22: map_2(f,nil_0()) -> nil_0() r23: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r24: filter_2(f,nil_0()) -> nil_0() r25: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r26: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r27: 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} {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(plus_0(),y) -> plus_1(y) r12: app(plus_1(x1),y) -> plus_2(x1,y) r13: app(s_0(),y) -> s_1(y) r14: app(times_0(),y) -> times_1(y) r15: app(times_1(x1),y) -> times_2(x1,y) r16: times_2(x,|0|_0()) -> |0|_0() r17: times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) r18: plus_2(x,|0|_0()) -> x r19: plus_2(|0|_0(),x) -> x r20: plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) r21: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) r22: map_2(f,nil_0()) -> nil_0() r23: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r24: filter_2(f,nil_0()) -> nil_0() r25: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r26: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r27: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r5, r24 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: app#_A(x1,x2) = max{23, x1 + 21, x2 + 10} filter_1_A(x1) = max{43, x1 + 18} filter_2#_A(x1,x2) = max{x1 + 24, x2 + 3} cons_2_A(x1,x2) = max{x1 + 17, x2 + 17} map_1_A(x1) = max{65, x1 + 2} map_2#_A(x1,x2) = max{66, x1 + 22, x2 - 6} filter2_3_A(x1,x2,x3) = max{x2 + 19, x3 + 19} filter2_4#_A(x1,x2,x3,x4) = max{x2 + 24, x3 - 1, x4 + 3} false_0_A = 20 app_A(x1,x2) = max{64, x2 + 19} true_0_A = 20 filter2_0_A = 3 filter2_1_A(x1) = max{2, x1 + 1} filter_2_A(x1,x2) = 42 nil_0_A = 41 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: app#_A(x1,x2) = x1 + x2 filter_1_A(x1) = x1 + 3 filter_2#_A(x1,x2) = x1 + x2 + 3 cons_2_A(x1,x2) = x1 + x2 + 10 map_1_A(x1) = x1 + 9 map_2#_A(x1,x2) = x1 + x2 filter2_3_A(x1,x2,x3) = x1 + x2 + x3 + 6 filter2_4#_A(x1,x2,x3,x4) = x2 + x4 + 3 false_0_A() = 1 app_A(x1,x2) = x1 + x2 + 1 true_0_A() = 1 filter2_0_A() = 3 filter2_1_A(x1) = x1 + 1 filter_2_A(x1,x2) = x1 + x2 + 9 nil_0_A() = 12 app#!_A(x1,x2) = x1 + 20 filter_1!_A(x1) = 14 filter_2#!_A(x1,x2) = x2 + 1 cons_2!_A(x1,x2) = x2 + 18 map_1!_A(x1) = x1 + 19 map_2#!_A(x1,x2) = 19 filter2_3!_A(x1,x2,x3) = 16 filter2_4#!_A(x1,x2,x3,x4) = x4 + 10 false_0!_A() = 0 app!_A(x1,x2) = x1 + 12 true_0!_A() = 0 filter2_0!_A() = 0 filter2_1!_A(x1) = 14 filter_2!_A(x1,x2) = x2 + 21 nil_0!_A() = 32 partial status: pi(app#) = [2] pi(filter_1) = [1] pi(filter_2#) = [2] pi(cons_2) = [1, 2] pi(map_1) = [1] pi(map_2#) = [1] pi(filter2_3) = [3] pi(filter2_4#) = [] pi(false_0) = [] pi(app) = [2] pi(true_0) = [] pi(filter2_0) = [] pi(filter2_1) = [1] pi(filter_2) = [] pi(nil_0) = [] The following rules are removed: p1, p2, p3, p5, p6, p7, p8, p9 -- 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) 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(plus_0(),y) -> plus_1(y) r12: app(plus_1(x1),y) -> plus_2(x1,y) r13: app(s_0(),y) -> s_1(y) r14: app(times_0(),y) -> times_1(y) r15: app(times_1(x1),y) -> times_2(x1,y) r16: times_2(x,|0|_0()) -> |0|_0() r17: times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) r18: plus_2(x,|0|_0()) -> x r19: plus_2(|0|_0(),x) -> x r20: plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) r21: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) r22: map_2(f,nil_0()) -> nil_0() r23: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r24: filter_2(f,nil_0()) -> nil_0() r25: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r26: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r27: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The estimated dependency graph contains the following SCCs: {p1} -- 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(plus_0(),y) -> plus_1(y) r12: app(plus_1(x1),y) -> plus_2(x1,y) r13: app(s_0(),y) -> s_1(y) r14: app(times_0(),y) -> times_1(y) r15: app(times_1(x1),y) -> times_2(x1,y) r16: times_2(x,|0|_0()) -> |0|_0() r17: times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) r18: plus_2(x,|0|_0()) -> x r19: plus_2(|0|_0(),x) -> x r20: plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) r21: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) r22: map_2(f,nil_0()) -> nil_0() r23: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r24: filter_2(f,nil_0()) -> nil_0() r25: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r26: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r27: 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) = 1 cons_2_A(x1,x2) = max{11, x1 - 32} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: map_2#_A(x1,x2) = x2 cons_2_A(x1,x2) = x1 + x2 + 5 map_2#!_A(x1,x2) = x2 + 4 cons_2!_A(x1,x2) = x1 + x2 + 5 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: times_2#(x,s_1(y)) -> times_2#(x,y) 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(plus_0(),y) -> plus_1(y) r12: app(plus_1(x1),y) -> plus_2(x1,y) r13: app(s_0(),y) -> s_1(y) r14: app(times_0(),y) -> times_1(y) r15: app(times_1(x1),y) -> times_2(x1,y) r16: times_2(x,|0|_0()) -> |0|_0() r17: times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) r18: plus_2(x,|0|_0()) -> x r19: plus_2(|0|_0(),x) -> x r20: plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) r21: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) r22: map_2(f,nil_0()) -> nil_0() r23: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r24: filter_2(f,nil_0()) -> nil_0() r25: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r26: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r27: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r24 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: times_2#_A(x1,x2) = 1 s_1_A(x1) = 16 filter_2_A(x1,x2) = 11 nil_0_A = 1 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: times_2#_A(x1,x2) = x2 s_1_A(x1) = x1 + 4 filter_2_A(x1,x2) = x2 + 14 nil_0_A() = 8 times_2#!_A(x1,x2) = x2 + 7 s_1!_A(x1) = 6 filter_2!_A(x1,x2) = 6 nil_0!_A() = 0 partial status: pi(times_2#) = [] pi(s_1) = [] pi(filter_2) = [] pi(nil_0) = [] 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: plus_2#(x,s_1(y)) -> plus_2#(x,y) p2: plus_2#(s_1(x),y) -> plus_2#(x,y) 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(plus_0(),y) -> plus_1(y) r12: app(plus_1(x1),y) -> plus_2(x1,y) r13: app(s_0(),y) -> s_1(y) r14: app(times_0(),y) -> times_1(y) r15: app(times_1(x1),y) -> times_2(x1,y) r16: times_2(x,|0|_0()) -> |0|_0() r17: times_2(x,s_1(y)) -> plus_2(times_2(x,y),x) r18: plus_2(x,|0|_0()) -> x r19: plus_2(|0|_0(),x) -> x r20: plus_2(x,s_1(y)) -> s_1(plus_2(x,y)) r21: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) r22: map_2(f,nil_0()) -> nil_0() r23: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r24: filter_2(f,nil_0()) -> nil_0() r25: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r26: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r27: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r24 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: plus_2#_A(x1,x2) = max{3, x1 - 13} s_1_A(x1) = max{12, x1 + 4} filter_2_A(x1,x2) = max{x1 + 6, x2 - 13} nil_0_A = 3 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus_2#_A(x1,x2) = x1 + x2 s_1_A(x1) = x1 + 4 filter_2_A(x1,x2) = x2 + 14 nil_0_A() = 8 plus_2#!_A(x1,x2) = x1 + x2 s_1!_A(x1) = 7 filter_2!_A(x1,x2) = x1 + x2 + 9 nil_0!_A() = 0 partial status: pi(plus_2#) = [] pi(s_1) = [1] pi(filter_2) = [] pi(nil_0) = [] The following rules are removed: p1, p2 Then no dependency pair remains.