YES We show the termination of the TRS R: 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(sum(),app(app(cons(),x),xs)) -> app(app(plus(),x),app(sum(),xs)) app(size(),app(app(node(),x),xs)) -> app(s(),app(sum(),app(app(map(),size()),xs))) app(app(plus(),|0|()),x) -> |0|() app(app(plus(),app(s(),x)),y) -> app(s(),app(app(plus(),x),y)) 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(map_0(),y) -> map_1(y) app(map_1(x1),y) -> map_2(x1,y) app(node_0(),y) -> node_1(y) app(node_1(x1),y) -> node_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(size_0(),y) -> size_1(y) app(sum_0(),y) -> sum_1(y) map_2(f,nil_0()) -> nil_0() map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) plus_2(|0|_0(),x) -> |0|_0() plus_2(s_1(x),y) -> s_1(plus_2(x,y)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: app#(map_1(x1),y) -> map_2#(x1,y) p2: app#(plus_1(x1),y) -> plus_2#(x1,y) p3: app#(size_0(),y) -> size_1#(y) p4: app#(sum_0(),y) -> sum_1#(y) p5: map_2#(f,cons_2(x,xs)) -> app#(f,x) p6: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p7: sum_1#(cons_2(x,xs)) -> plus_2#(x,sum_1(xs)) p8: sum_1#(cons_2(x,xs)) -> sum_1#(xs) p9: size_1#(node_2(x,xs)) -> sum_1#(map_2(size_0(),xs)) p10: size_1#(node_2(x,xs)) -> map_2#(size_0(),xs) p11: 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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) The estimated dependency graph contains the following SCCs: {p1, p3, p5, p6, p10} {p8} {p11} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: app#(map_1(x1),y) -> map_2#(x1,y) p2: map_2#(f,cons_2(x,xs)) -> map_2#(f,xs) p3: map_2#(f,cons_2(x,xs)) -> app#(f,x) p4: app#(size_0(),y) -> size_1#(y) p5: size_1#(node_2(x,xs)) -> map_2#(size_0(),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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) The set of usable rules consists of r1, r2, r5, r6, r7, r8, r9, r16, r17 Take the reduction pair: generalized weighted path order (>=MG, >MG) base order 1: max/plus interpretation on natural numbers: app#_A(x1,x2) = max{13, x1 - 77} map_1_A(x1) = x1 + 91 map_2#_A(x1,x2) = max{13, x1 - 77} cons_2_A(x1,x2) = max{12, x1 - 16, x2 - 16} size_0_A = 1 size_1#_A(x1) = 13 node_2_A(x1,x2) = max{14, x1 - 75, x2 - 75} app_A(x1,x2) = max{15, x1 - 6, x2 + 4} cons_0_A = 4 cons_1_A(x1) = max{5, x1 - 1} node_0_A = 4 node_1_A(x1) = max{5, x1 - 1} plus_0_A = 7 plus_1_A(x1) = max{8, x1 - 1} plus_2_A(x1,x2) = max{10, x1 - 34, x2 - 26} s_0_A = 7 s_1_A(x1) = max{8, x1 - 35} |0|_0_A = 0 base order 2: precedence: app# = map_2# = size_1# > node_2 = s_0 > size_0 > map_1 > app > cons_2 = node_1 > cons_1 = node_0 > cons_0 = plus_2 > plus_1 = s_1 = |0|_0 > plus_0 partial status: pi(app#) = [] pi(map_1) = [1] pi(map_2#) = [] pi(cons_2) = [] pi(size_0) = [] pi(size_1#) = [] pi(node_2) = [] pi(app) = [] pi(cons_0) = [] pi(cons_1) = [] pi(node_0) = [] pi(node_1) = [] pi(plus_0) = [] pi(plus_1) = [] pi(plus_2) = [] pi(s_0) = [] pi(s_1) = [] pi(|0|_0) = [] The following rules are removed: p1 -- 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: map_2#(f,cons_2(x,xs)) -> app#(f,x) p3: app#(size_0(),y) -> size_1#(y) p4: size_1#(node_2(x,xs)) -> map_2#(size_0(),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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) 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) p2: map_2#(f,cons_2(x,xs)) -> app#(f,x) p3: app#(size_0(),y) -> size_1#(y) p4: size_1#(node_2(x,xs)) -> map_2#(size_0(),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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) The set of usable rules consists of r1, r5, r7, r8, r16, r17 Take the reduction pair: generalized weighted path order (>=MG, >MG) base order 1: max/plus interpretation on natural numbers: map_2#_A(x1,x2) = max{4, x1 - 10, x2 - 15} cons_2_A(x1,x2) = max{x1 + 26, x2 + 5} app#_A(x1,x2) = max{11, x1 - 10, x2 + 9} size_0_A = 9 size_1#_A(x1) = max{10, x1 - 12} node_2_A(x1,x2) = max{10, x1 - 50, x2 - 2} app_A(x1,x2) = max{27, x1 - 27, x2 - 27} cons_0_A = 1 cons_1_A(x1) = max{2, x1 - 28} node_0_A = 1 node_1_A(x1) = 9 plus_0_A = 4 plus_1_A(x1) = max{5, x1 - 28} plus_2_A(x1,x2) = max{6, x1 - 56, x2 - 28} |0|_0_A = 0 s_1_A(x1) = max{2, x1} base order 2: precedence: size_1# = node_2 = app > map_2# = size_0 > app# = node_1 > node_0 > cons_2 > cons_1 > cons_0 = plus_2 > plus_1 = |0|_0 = s_1 > plus_0 partial status: pi(map_2#) = [] pi(cons_2) = [1, 2] pi(app#) = [2] pi(size_0) = [] pi(size_1#) = [] pi(node_2) = [] pi(app) = [] pi(cons_0) = [] pi(cons_1) = [] pi(node_0) = [] pi(node_1) = [] pi(plus_0) = [] pi(plus_1) = [] pi(plus_2) = [] pi(|0|_0) = [] pi(s_1) = [] The following rules are removed: p2 -- 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: app#(size_0(),y) -> size_1#(y) p3: size_1#(node_2(x,xs)) -> map_2#(size_0(),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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) 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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) The set of usable rules consists of r1, r2, r3, r5, r6, r7, r8, r9, r16, r17 Take the reduction pair: generalized weighted path order (>=MG, >MG) base order 1: max/plus interpretation on natural numbers: map_2#_A(x1,x2) = max{x1 + 8, x2 + 20} cons_2_A(x1,x2) = max{6, x1 - 12, x2} app_A(x1,x2) = max{9, x1 - 10, x2 + 7} cons_0_A = 8 cons_1_A(x1) = max{9, x1 - 1} map_0_A = 8 map_1_A(x1) = max{9, x1 - 1} node_0_A = 1 node_1_A(x1) = max{2, x1 - 1} node_2_A(x1,x2) = max{3, x1 - 30, x2 - 51} plus_0_A = 3 plus_1_A(x1) = max{4, x1 - 1} plus_2_A(x1,x2) = max{5, x1 - 20, x2 - 17} s_0_A = 2 s_1_A(x1) = max{3, x1 - 21} |0|_0_A = 0 base order 2: precedence: app > map_2# > cons_2 = map_1 > node_2 = plus_2 > s_1 = |0|_0 > cons_0 > cons_1 = map_0 = node_1 = plus_1 = s_0 > node_0 = plus_0 partial status: pi(map_2#) = [2] pi(cons_2) = [2] pi(app) = [2] pi(cons_0) = [] pi(cons_1) = [] pi(map_0) = [] pi(map_1) = [] pi(node_0) = [] pi(node_1) = [] pi(node_2) = [] pi(plus_0) = [] pi(plus_1) = [] pi(plus_2) = [] pi(s_0) = [] pi(s_1) = [] pi(|0|_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: sum_1#(cons_2(x,xs)) -> sum_1#(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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) The set of usable rules consists of r1, r3, r5, r6, r7, r8, r9, r16, r17 Take the reduction pair: generalized weighted path order (>=MG, >MG) base order 1: max/plus interpretation on natural numbers: sum_1#_A(x1) = x1 + 20 cons_2_A(x1,x2) = max{x1 - 16, x2 + 21} app_A(x1,x2) = max{15, x1 - 3, x2 - 1} cons_0_A = 2 cons_1_A(x1) = max{1, x1 - 2} map_0_A = 1 map_1_A(x1) = max{2, x1 - 1} node_0_A = 1 node_1_A(x1) = max{2, x1 - 80} node_2_A(x1,x2) = max{14, x1 - 84, x2 - 84} plus_0_A = 4 plus_1_A(x1) = max{12, x1 - 2} plus_2_A(x1,x2) = max{13, x1 - 39, x2 - 28} s_0_A = 2 s_1_A(x1) = max{11, x1 - 40} |0|_0_A = 0 base order 2: precedence: node_0 = node_2 > app > cons_2 = map_1 = node_1 > sum_1# = cons_1 = map_0 > cons_0 = plus_2 > plus_1 = s_1 = |0|_0 > plus_0 = s_0 partial status: pi(sum_1#) = [1] pi(cons_2) = [2] pi(app) = [] pi(cons_0) = [] pi(cons_1) = [] pi(map_0) = [] pi(map_1) = [] pi(node_0) = [] pi(node_1) = [] pi(node_2) = [] pi(plus_0) = [] pi(plus_1) = [] pi(plus_2) = [] pi(s_0) = [] pi(s_1) = [] pi(|0|_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#(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(map_0(),y) -> map_1(y) r4: app(map_1(x1),y) -> map_2(x1,y) r5: app(node_0(),y) -> node_1(y) r6: app(node_1(x1),y) -> node_2(x1,y) r7: app(plus_0(),y) -> plus_1(y) r8: app(plus_1(x1),y) -> plus_2(x1,y) r9: app(s_0(),y) -> s_1(y) r10: app(size_0(),y) -> size_1(y) r11: app(sum_0(),y) -> sum_1(y) r12: map_2(f,nil_0()) -> nil_0() r13: map_2(f,cons_2(x,xs)) -> cons_2(app(f,x),map_2(f,xs)) r14: sum_1(cons_2(x,xs)) -> plus_2(x,sum_1(xs)) r15: size_1(node_2(x,xs)) -> s_1(sum_1(map_2(size_0(),xs))) r16: plus_2(|0|_0(),x) -> |0|_0() r17: plus_2(s_1(x),y) -> s_1(plus_2(x,y)) The set of usable rules consists of r1, r2, r5, r6, r7 Take the reduction pair: generalized weighted path order (>=MG, >MG) base order 1: max/plus interpretation on natural numbers: plus_2#_A(x1,x2) = max{x1 + 6, x2 + 13} s_1_A(x1) = max{11, x1 + 7} app_A(x1,x2) = max{11, x1 - 13, x2 - 1} cons_0_A = 2 cons_1_A(x1) = max{3, x1 - 1} cons_2_A(x1,x2) = max{4, x1 - 18, x2 - 6} node_0_A = 1 node_1_A(x1) = max{2, x1 - 2} node_2_A(x1,x2) = max{11, x1 - 44, x2 - 44} plus_0_A = 28 plus_1_A(x1) = max{14, x1 - 18} base order 2: precedence: cons_2 > app > plus_2# = cons_1 = node_0 = node_2 > s_1 = cons_0 = node_1 > plus_1 > plus_0 partial status: pi(plus_2#) = [1] pi(s_1) = [] pi(app) = [] pi(cons_0) = [] pi(cons_1) = [] pi(cons_2) = [] pi(node_0) = [] pi(node_1) = [] pi(node_2) = [] pi(plus_0) = [] pi(plus_1) = [] The following rules are removed: p1 Then no dependency pair remains.