YES We show the termination of the TRS R: app(app(le(),|0|()),y) -> true() app(app(le(),app(s(),x)),|0|()) -> false() app(app(le(),app(s(),x)),app(s(),y)) -> app(app(le(),x),y) app(pred(),app(s(),x)) -> x app(app(minus(),x),|0|()) -> x app(app(minus(),x),app(s(),y)) -> app(pred(),app(app(minus(),x),y)) app(app(gcd(),|0|()),y) -> y app(app(gcd(),app(s(),x)),|0|()) -> app(s(),x) app(app(gcd(),app(s(),x)),app(s(),y)) -> app(app(app(if_gcd(),app(app(le(),y),x)),app(s(),x)),app(s(),y)) app(app(app(if_gcd(),true()),app(s(),x)),app(s(),y)) -> app(app(gcd(),app(app(minus(),x),y)),app(s(),y)) app(app(app(if_gcd(),false()),app(s(),x)),app(s(),y)) -> app(app(gcd(),app(app(minus(),y),x)),app(s(),x)) 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(gcd_0(),y) -> gcd_1(y) app(gcd_1(x1),y) -> gcd_2(x1,y) app(if_gcd_0(),y) -> if_gcd_1(y) app(if_gcd_1(x1),y) -> if_gcd_2(x1,y) app(if_gcd_2(x1,x2),y) -> if_gcd_3(x1,x2,y) app(le_0(),y) -> le_1(y) app(le_1(x1),y) -> le_2(x1,y) app(map_0(),y) -> map_1(y) app(map_1(x1),y) -> map_2(x1,y) app(minus_0(),y) -> minus_1(y) app(minus_1(x1),y) -> minus_2(x1,y) app(pred_0(),y) -> pred_1(y) app(s_0(),y) -> s_1(y) le_2(|0|_0(),y) -> true_0() le_2(s_1(x),|0|_0()) -> false_0() le_2(s_1(x),s_1(y)) -> le_2(x,y) pred_1(s_1(x)) -> x minus_2(x,|0|_0()) -> x minus_2(x,s_1(y)) -> pred_1(minus_2(x,y)) gcd_2(|0|_0(),y) -> y gcd_2(s_1(x),|0|_0()) -> s_1(x) gcd_2(s_1(x),s_1(y)) -> if_gcd_3(le_2(y,x),s_1(x),s_1(y)) if_gcd_3(true_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(x,y),s_1(y)) if_gcd_3(false_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(y,x),s_1(x)) 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#(gcd_1(x1),y) -> gcd_2#(x1,y) p4: app#(if_gcd_2(x1,x2),y) -> if_gcd_3#(x1,x2,y) p5: app#(le_1(x1),y) -> le_2#(x1,y) p6: app#(map_1(x1),y) -> map_2#(x1,y) p7: app#(minus_1(x1),y) -> minus_2#(x1,y) p8: app#(pred_0(),y) -> pred_1#(y) p9: le_2#(s_1(x),s_1(y)) -> le_2#(x,y) p10: minus_2#(x,s_1(y)) -> pred_1#(minus_2(x,y)) p11: minus_2#(x,s_1(y)) -> minus_2#(x,y) p12: gcd_2#(s_1(x),s_1(y)) -> if_gcd_3#(le_2(y,x),s_1(x),s_1(y)) p13: gcd_2#(s_1(x),s_1(y)) -> le_2#(y,x) p14: if_gcd_3#(true_0(),s_1(x),s_1(y)) -> gcd_2#(minus_2(x,y),s_1(y)) p15: if_gcd_3#(true_0(),s_1(x),s_1(y)) -> minus_2#(x,y) p16: if_gcd_3#(false_0(),s_1(x),s_1(y)) -> gcd_2#(minus_2(y,x),s_1(x)) p17: if_gcd_3#(false_0(),s_1(x),s_1(y)) -> minus_2#(y,x) p18: map_2#(f,cons_2(x,xs)) -> app#(f,x) p19: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p20: filter_2#(f,cons_2(x,xs)) -> filter2_4#(app(f,x),f,x,xs) p21: filter_2#(f,cons_2(x,xs)) -> app#(f,x) p22: filter2_4#(true_0(),f,x,xs) -> filter_2#(f,xs) p23: 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(gcd_0(),y) -> gcd_1(y) r10: app(gcd_1(x1),y) -> gcd_2(x1,y) r11: app(if_gcd_0(),y) -> if_gcd_1(y) r12: app(if_gcd_1(x1),y) -> if_gcd_2(x1,y) r13: app(if_gcd_2(x1,x2),y) -> if_gcd_3(x1,x2,y) r14: app(le_0(),y) -> le_1(y) r15: app(le_1(x1),y) -> le_2(x1,y) r16: app(map_0(),y) -> map_1(y) r17: app(map_1(x1),y) -> map_2(x1,y) r18: app(minus_0(),y) -> minus_1(y) r19: app(minus_1(x1),y) -> minus_2(x1,y) r20: app(pred_0(),y) -> pred_1(y) r21: app(s_0(),y) -> s_1(y) r22: le_2(|0|_0(),y) -> true_0() r23: le_2(s_1(x),|0|_0()) -> false_0() r24: le_2(s_1(x),s_1(y)) -> le_2(x,y) r25: pred_1(s_1(x)) -> x r26: minus_2(x,|0|_0()) -> x r27: minus_2(x,s_1(y)) -> pred_1(minus_2(x,y)) r28: gcd_2(|0|_0(),y) -> y r29: gcd_2(s_1(x),|0|_0()) -> s_1(x) r30: gcd_2(s_1(x),s_1(y)) -> if_gcd_3(le_2(y,x),s_1(x),s_1(y)) r31: if_gcd_3(true_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(x,y),s_1(y)) r32: if_gcd_3(false_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(y,x),s_1(x)) r33: map_2(f,nil_0()) -> nil_0() r34: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r35: filter_2(f,nil_0()) -> nil_0() r36: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r37: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r38: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The estimated dependency graph contains the following SCCs: {p1, p2, p6, p18, p19, p20, p21, p22, p23} {p12, p14, p16} {p9} {p11} -- 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(gcd_0(),y) -> gcd_1(y) r10: app(gcd_1(x1),y) -> gcd_2(x1,y) r11: app(if_gcd_0(),y) -> if_gcd_1(y) r12: app(if_gcd_1(x1),y) -> if_gcd_2(x1,y) r13: app(if_gcd_2(x1,x2),y) -> if_gcd_3(x1,x2,y) r14: app(le_0(),y) -> le_1(y) r15: app(le_1(x1),y) -> le_2(x1,y) r16: app(map_0(),y) -> map_1(y) r17: app(map_1(x1),y) -> map_2(x1,y) r18: app(minus_0(),y) -> minus_1(y) r19: app(minus_1(x1),y) -> minus_2(x1,y) r20: app(pred_0(),y) -> pred_1(y) r21: app(s_0(),y) -> s_1(y) r22: le_2(|0|_0(),y) -> true_0() r23: le_2(s_1(x),|0|_0()) -> false_0() r24: le_2(s_1(x),s_1(y)) -> le_2(x,y) r25: pred_1(s_1(x)) -> x r26: minus_2(x,|0|_0()) -> x r27: minus_2(x,s_1(y)) -> pred_1(minus_2(x,y)) r28: gcd_2(|0|_0(),y) -> y r29: gcd_2(s_1(x),|0|_0()) -> s_1(x) r30: gcd_2(s_1(x),s_1(y)) -> if_gcd_3(le_2(y,x),s_1(x),s_1(y)) r31: if_gcd_3(true_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(x,y),s_1(y)) r32: if_gcd_3(false_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(y,x),s_1(x)) r33: map_2(f,nil_0()) -> nil_0() r34: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r35: filter_2(f,nil_0()) -> nil_0() r36: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r37: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r38: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r29 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: app#_A(x1,x2) = max{20, x2 + 1} filter_1_A(x1) = 30 filter_2#_A(x1,x2) = max{18, x2 - 20} cons_2_A(x1,x2) = max{61, x1 + 22, x2 + 38} map_1_A(x1) = x1 + 66 map_2#_A(x1,x2) = max{19, x2 - 1} filter2_3_A(x1,x2,x3) = max{2, x1 - 67, x2 - 38} filter2_4#_A(x1,x2,x3,x4) = max{19, x4 - 1} false_0_A = 96 app_A(x1,x2) = max{x1 - 38, x2 + 65} true_0_A = 63 gcd_2_A(x1,x2) = max{36, x1} s_1_A(x1) = 35 |0|_0_A = 97 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 filter_1_A(x1) = x1 + 5 filter_2#_A(x1,x2) = x1 cons_2_A(x1,x2) = x1 + 11 map_1_A(x1) = x1 + 9 map_2#_A(x1,x2) = x1 filter2_3_A(x1,x2,x3) = x1 + x2 + x3 + 6 filter2_4#_A(x1,x2,x3,x4) = x2 false_0_A() = 16 app_A(x1,x2) = x1 + x2 + 3 true_0_A() = 11 gcd_2_A(x1,x2) = x1 + 9 s_1_A(x1) = x1 + 5 |0|_0_A() = 1 app#!_A(x1,x2) = x1 + 27 filter_1!_A(x1) = 1 filter_2#!_A(x1,x2) = x2 + 33 cons_2!_A(x1,x2) = x1 + 14 map_1!_A(x1) = x1 + 16 map_2#!_A(x1,x2) = x2 + 15 filter2_3!_A(x1,x2,x3) = 35 filter2_4#!_A(x1,x2,x3,x4) = x4 + 34 false_0!_A() = 1 app!_A(x1,x2) = x1 + 7 true_0!_A() = 13 gcd_2!_A(x1,x2) = x1 + 2 s_1!_A(x1) = 7 |0|_0!_A() = 14 partial status: pi(app#) = [2] pi(filter_1) = [] pi(filter_2#) = [] pi(cons_2) = [] pi(map_1) = [1] pi(map_2#) = [] pi(filter2_3) = [] pi(filter2_4#) = [] pi(false_0) = [] pi(app) = [2] pi(true_0) = [] pi(gcd_2) = [1] pi(s_1) = [] pi(|0|_0) = [] The following rules are removed: p1, p2, p3, p4, p5, p6, p7, p8, p9 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: gcd_2#(s_1(x),s_1(y)) -> if_gcd_3#(le_2(y,x),s_1(x),s_1(y)) p2: if_gcd_3#(false_0(),s_1(x),s_1(y)) -> gcd_2#(minus_2(y,x),s_1(x)) p3: if_gcd_3#(true_0(),s_1(x),s_1(y)) -> gcd_2#(minus_2(x,y),s_1(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(gcd_0(),y) -> gcd_1(y) r10: app(gcd_1(x1),y) -> gcd_2(x1,y) r11: app(if_gcd_0(),y) -> if_gcd_1(y) r12: app(if_gcd_1(x1),y) -> if_gcd_2(x1,y) r13: app(if_gcd_2(x1,x2),y) -> if_gcd_3(x1,x2,y) r14: app(le_0(),y) -> le_1(y) r15: app(le_1(x1),y) -> le_2(x1,y) r16: app(map_0(),y) -> map_1(y) r17: app(map_1(x1),y) -> map_2(x1,y) r18: app(minus_0(),y) -> minus_1(y) r19: app(minus_1(x1),y) -> minus_2(x1,y) r20: app(pred_0(),y) -> pred_1(y) r21: app(s_0(),y) -> s_1(y) r22: le_2(|0|_0(),y) -> true_0() r23: le_2(s_1(x),|0|_0()) -> false_0() r24: le_2(s_1(x),s_1(y)) -> le_2(x,y) r25: pred_1(s_1(x)) -> x r26: minus_2(x,|0|_0()) -> x r27: minus_2(x,s_1(y)) -> pred_1(minus_2(x,y)) r28: gcd_2(|0|_0(),y) -> y r29: gcd_2(s_1(x),|0|_0()) -> s_1(x) r30: gcd_2(s_1(x),s_1(y)) -> if_gcd_3(le_2(y,x),s_1(x),s_1(y)) r31: if_gcd_3(true_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(x,y),s_1(y)) r32: if_gcd_3(false_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(y,x),s_1(x)) r33: map_2(f,nil_0()) -> nil_0() r34: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r35: filter_2(f,nil_0()) -> nil_0() r36: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r37: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r38: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r7, r9, r14, r16, r20, r23, r25, r26, r27, r35 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: gcd_2#_A(x1,x2) = max{x1 + 1, x2 - 14} s_1_A(x1) = x1 + 34 if_gcd_3#_A(x1,x2,x3) = max{35, x2 - 1, x3 - 14} le_2_A(x1,x2) = max{75, x1 + 36, x2 + 33} false_0_A = 71 minus_2_A(x1,x2) = max{17, x1 + 1} true_0_A = 76 app_A(x1,x2) = max{x1 + 11, x2 + 78} filter2_2_A(x1,x2) = max{76, x1 + 1} filter2_3_A(x1,x2,x3) = max{2, x1 - 5} gcd_0_A = 80 gcd_1_A(x1) = max{79, x1 + 67} le_0_A = 1 le_1_A(x1) = x1 + 37 map_0_A = 80 map_1_A(x1) = 79 pred_0_A = 1 pred_1_A(x1) = max{2, x1 - 18} |0|_0_A = 13 filter_2_A(x1,x2) = max{81, x1 + 4} nil_0_A = 80 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: gcd_2#_A(x1,x2) = 0 s_1_A(x1) = x1 + 12 if_gcd_3#_A(x1,x2,x3) = 0 le_2_A(x1,x2) = x1 + 3 false_0_A() = 1 minus_2_A(x1,x2) = x1 + 7 true_0_A() = 5 app_A(x1,x2) = x1 + x2 + 2 filter2_2_A(x1,x2) = x1 + x2 + 7 filter2_3_A(x1,x2,x3) = x1 + x2 + x3 gcd_0_A() = 1 gcd_1_A(x1) = x1 + 1 le_0_A() = 1 le_1_A(x1) = x1 map_0_A() = 0 map_1_A(x1) = x1 pred_0_A() = 1 pred_1_A(x1) = x1 |0|_0_A() = 1 filter_2_A(x1,x2) = x2 + 19 nil_0_A() = 9 gcd_2#!_A(x1,x2) = x1 + x2 + 1 s_1!_A(x1) = x1 + 3 if_gcd_3#!_A(x1,x2,x3) = x2 + x3 le_2!_A(x1,x2) = x1 + 2 false_0!_A() = 4 minus_2!_A(x1,x2) = 18 true_0!_A() = 19 app!_A(x1,x2) = 17 filter2_2!_A(x1,x2) = 15 filter2_3!_A(x1,x2,x3) = x1 + x3 + 14 gcd_0!_A() = 0 gcd_1!_A(x1) = 16 le_0!_A() = 0 le_1!_A(x1) = 16 map_0!_A() = 19 map_1!_A(x1) = x1 + 18 pred_0!_A() = 0 pred_1!_A(x1) = x1 + 18 |0|_0!_A() = 0 filter_2!_A(x1,x2) = x2 + 5 nil_0!_A() = 13 partial status: pi(gcd_2#) = [] pi(s_1) = [1] pi(if_gcd_3#) = [] pi(le_2) = [] pi(false_0) = [] pi(minus_2) = [] pi(true_0) = [] pi(app) = [1] pi(filter2_2) = [] pi(filter2_3) = [] pi(gcd_0) = [] pi(gcd_1) = [1] pi(le_0) = [] pi(le_1) = [1] pi(map_0) = [] pi(map_1) = [] pi(pred_0) = [] pi(pred_1) = [] pi(|0|_0) = [] pi(filter_2) = [1] 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: le_2#(s_1(x),s_1(y)) -> le_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(gcd_0(),y) -> gcd_1(y) r10: app(gcd_1(x1),y) -> gcd_2(x1,y) r11: app(if_gcd_0(),y) -> if_gcd_1(y) r12: app(if_gcd_1(x1),y) -> if_gcd_2(x1,y) r13: app(if_gcd_2(x1,x2),y) -> if_gcd_3(x1,x2,y) r14: app(le_0(),y) -> le_1(y) r15: app(le_1(x1),y) -> le_2(x1,y) r16: app(map_0(),y) -> map_1(y) r17: app(map_1(x1),y) -> map_2(x1,y) r18: app(minus_0(),y) -> minus_1(y) r19: app(minus_1(x1),y) -> minus_2(x1,y) r20: app(pred_0(),y) -> pred_1(y) r21: app(s_0(),y) -> s_1(y) r22: le_2(|0|_0(),y) -> true_0() r23: le_2(s_1(x),|0|_0()) -> false_0() r24: le_2(s_1(x),s_1(y)) -> le_2(x,y) r25: pred_1(s_1(x)) -> x r26: minus_2(x,|0|_0()) -> x r27: minus_2(x,s_1(y)) -> pred_1(minus_2(x,y)) r28: gcd_2(|0|_0(),y) -> y r29: gcd_2(s_1(x),|0|_0()) -> s_1(x) r30: gcd_2(s_1(x),s_1(y)) -> if_gcd_3(le_2(y,x),s_1(x),s_1(y)) r31: if_gcd_3(true_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(x,y),s_1(y)) r32: if_gcd_3(false_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(y,x),s_1(x)) r33: map_2(f,nil_0()) -> nil_0() r34: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r35: filter_2(f,nil_0()) -> nil_0() r36: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r37: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r38: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r18, r35 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: le_2#_A(x1,x2) = max{x1 + 6, x2 + 6} s_1_A(x1) = x1 + 4 app_A(x1,x2) = max{x1 - 10, x2 + 20} minus_0_A = 8 minus_1_A(x1) = x1 + 17 filter_2_A(x1,x2) = max{6, x2 - 32} nil_0_A = 2 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: le_2#_A(x1,x2) = 0 s_1_A(x1) = 3 app_A(x1,x2) = x1 + x2 + 1 minus_0_A() = 12 minus_1_A(x1) = x1 + 11 filter_2_A(x1,x2) = x1 + x2 + 10 nil_0_A() = 6 le_2#!_A(x1,x2) = x2 + 6 s_1!_A(x1) = 5 app!_A(x1,x2) = x1 + 13 minus_0!_A() = 0 minus_1!_A(x1) = 24 filter_2!_A(x1,x2) = x2 + 7 nil_0!_A() = 0 partial status: pi(le_2#) = [] pi(s_1) = [] pi(app) = [2] pi(minus_0) = [] pi(minus_1) = [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: minus_2#(x,s_1(y)) -> minus_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(gcd_0(),y) -> gcd_1(y) r10: app(gcd_1(x1),y) -> gcd_2(x1,y) r11: app(if_gcd_0(),y) -> if_gcd_1(y) r12: app(if_gcd_1(x1),y) -> if_gcd_2(x1,y) r13: app(if_gcd_2(x1,x2),y) -> if_gcd_3(x1,x2,y) r14: app(le_0(),y) -> le_1(y) r15: app(le_1(x1),y) -> le_2(x1,y) r16: app(map_0(),y) -> map_1(y) r17: app(map_1(x1),y) -> map_2(x1,y) r18: app(minus_0(),y) -> minus_1(y) r19: app(minus_1(x1),y) -> minus_2(x1,y) r20: app(pred_0(),y) -> pred_1(y) r21: app(s_0(),y) -> s_1(y) r22: le_2(|0|_0(),y) -> true_0() r23: le_2(s_1(x),|0|_0()) -> false_0() r24: le_2(s_1(x),s_1(y)) -> le_2(x,y) r25: pred_1(s_1(x)) -> x r26: minus_2(x,|0|_0()) -> x r27: minus_2(x,s_1(y)) -> pred_1(minus_2(x,y)) r28: gcd_2(|0|_0(),y) -> y r29: gcd_2(s_1(x),|0|_0()) -> s_1(x) r30: gcd_2(s_1(x),s_1(y)) -> if_gcd_3(le_2(y,x),s_1(x),s_1(y)) r31: if_gcd_3(true_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(x,y),s_1(y)) r32: if_gcd_3(false_0(),s_1(x),s_1(y)) -> gcd_2(minus_2(y,x),s_1(x)) r33: map_2(f,nil_0()) -> nil_0() r34: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r35: filter_2(f,nil_0()) -> nil_0() r36: filter_2(f,cons_2(x,xs)) -> filter2_4(app(f,x),f,x,xs) r37: filter2_4(true_0(),f,x,xs) -> cons_2(x,filter_2(f,xs)) r38: filter2_4(false_0(),f,x,xs) -> filter_2(f,xs) The set of usable rules consists of r35 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: minus_2#_A(x1,x2) = x2 + 3 s_1_A(x1) = max{24, x1 + 3} filter_2_A(x1,x2) = 25 nil_0_A = 24 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: minus_2#_A(x1,x2) = 0 s_1_A(x1) = 2 filter_2_A(x1,x2) = x2 + 3 nil_0_A() = 3 minus_2#!_A(x1,x2) = 0 s_1!_A(x1) = x1 + 18 filter_2!_A(x1,x2) = 9 nil_0!_A() = 1 partial status: pi(minus_2#) = [2] pi(s_1) = [] pi(filter_2) = [] pi(nil_0) = [] The following rules are removed: p1 Then no dependency pair remains.