YES We show the termination of the TRS R: +(x,|0|()) -> x +(|0|(),x) -> x +(s(x),s(y)) -> s(s(+(x,y))) +(+(x,y),z) -> +(x,+(y,z)) *(x,|0|()) -> |0|() *(|0|(),x) -> |0|() *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) *(*(x,y),z) -> *(x,*(y,z)) sum(nil()) -> |0|() sum(cons(x,l)) -> +(x,sum(l)) prod(nil()) -> s(|0|()) prod(cons(x,l)) -> *(x,prod(l)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: +#(s(x),s(y)) -> +#(x,y) p2: +#(+(x,y),z) -> +#(x,+(y,z)) p3: +#(+(x,y),z) -> +#(y,z) p4: *#(s(x),s(y)) -> +#(*(x,y),+(x,y)) p5: *#(s(x),s(y)) -> *#(x,y) p6: *#(s(x),s(y)) -> +#(x,y) p7: *#(*(x,y),z) -> *#(x,*(y,z)) p8: *#(*(x,y),z) -> *#(y,z) p9: sum#(cons(x,l)) -> +#(x,sum(l)) p10: sum#(cons(x,l)) -> sum#(l) p11: prod#(cons(x,l)) -> *#(x,prod(l)) p12: prod#(cons(x,l)) -> prod#(l) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) The estimated dependency graph contains the following SCCs: {p10} {p12} {p5, p7, p8} {p1, p2, p3} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: sum#(cons(x,l)) -> sum#(l) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) 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!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: sum#_A(x1) = x1 cons_A(x1,x2) = x1 + x2 + 1 sum#!_A(x1) = x1 + 2 cons!_A(x1,x2) = 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: sum#_A(x1) = 0 cons_A(x1,x2) = max{0, x1 - 15, x2 - 84} sum#!_A(x1) = max{2, x1 - 15} cons!_A(x1,x2) = max{1, x2 - 14} partial status: pi(sum#) = [] 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: prod#(cons(x,l)) -> prod#(l) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) 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!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: prod#_A(x1) = x1 cons_A(x1,x2) = x1 + x2 + 1 prod#!_A(x1) = x1 + 6 cons!_A(x1,x2) = x2 + 5 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: prod#_A(x1) = x1 cons_A(x1,x2) = max{x1 - 5, x2} prod#!_A(x1) = max{7, x1 - 1} cons!_A(x1,x2) = max{x1 + 6, x2 - 31} partial status: pi(prod#) = [] 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: *#(*(x,y),z) -> *#(y,z) p2: *#(*(x,y),z) -> *#(x,*(y,z)) p3: *#(s(x),s(y)) -> *#(x,y) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) The set of usable rules consists of r1, r2, r5, r6 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!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: *#_A(x1,x2) = x1 *_A(x1,x2) = x1 + x2 + 2 s_A(x1) = x1 + 1 +_A(x1,x2) = x1 + x2 + 2 |0|_A() = 3 *#!_A(x1,x2) = x1 *!_A(x1,x2) = x1 + 3 s!_A(x1) = 5 +!_A(x1,x2) = 8 |0|!_A() = 0 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: *#_A(x1,x2) = max{0, x1 - 95} *_A(x1,x2) = max{94, x1 + 90, x2 + 87} s_A(x1) = x1 + 107 +_A(x1,x2) = max{202, x1 + 129, x2 + 57} |0|_A = 87 *#!_A(x1,x2) = max{1, x1 - 88} *!_A(x1,x2) = max{11, x1 - 87, x2 - 95} s!_A(x1) = max{38, x1 - 165} +!_A(x1,x2) = max{10, x1 - 71} |0|!_A = 2 partial status: pi(*#) = [] pi(*) = [2] pi(s) = [1] pi(+) = [1, 2] pi(|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: +#(s(x),s(y)) -> +#(x,y) p2: +#(+(x,y),z) -> +#(y,z) p3: +#(+(x,y),z) -> +#(x,+(y,z)) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) 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!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: +#_A(x1,x2) = x1 s_A(x1) = x1 + 1 +_A(x1,x2) = x1 + x2 +#!_A(x1,x2) = x1 + 3 s!_A(x1) = 2 +!_A(x1,x2) = 4 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: +#_A(x1,x2) = 0 s_A(x1) = x1 + 3 +_A(x1,x2) = 3 +#!_A(x1,x2) = 6 s!_A(x1) = max{5, x1 + 3} +!_A(x1,x2) = max{0, x1 - 4, x2 - 5} partial status: pi(+#) = [] pi(s) = [] pi(+) = [1, 2] The following rules are removed: p1 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: +#(+(x,y),z) -> +#(y,z) p2: +#(+(x,y),z) -> +#(x,+(y,z)) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: +#(+(x,y),z) -> +#(y,z) p2: +#(+(x,y),z) -> +#(x,+(y,z)) and R consists of: r1: +(x,|0|()) -> x r2: +(|0|(),x) -> x r3: +(s(x),s(y)) -> s(s(+(x,y))) r4: +(+(x,y),z) -> +(x,+(y,z)) r5: *(x,|0|()) -> |0|() r6: *(|0|(),x) -> |0|() r7: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r8: *(*(x,y),z) -> *(x,*(y,z)) r9: sum(nil()) -> |0|() r10: sum(cons(x,l)) -> +(x,sum(l)) r11: prod(nil()) -> s(|0|()) r12: prod(cons(x,l)) -> *(x,prod(l)) The set of usable rules consists of r1, r2, r3, r4 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!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: +#_A(x1,x2) = x1 + x2 +_A(x1,x2) = x1 + x2 + 4 |0|_A() = 3 s_A(x1) = 0 +#!_A(x1,x2) = x1 + 5 +!_A(x1,x2) = 4 |0|!_A() = 0 s!_A(x1) = 3 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: +#_A(x1,x2) = max{0, x1 - 22, x2 - 43} +_A(x1,x2) = max{x1 + 21, x2} |0|_A = 17 s_A(x1) = max{10, x1 - 34} +#!_A(x1,x2) = 0 +!_A(x1,x2) = 0 |0|!_A = 0 s!_A(x1) = max{0, x1 - 57} partial status: pi(+#) = [] pi(+) = [1, 2] pi(|0|) = [] pi(s) = [1] The following rules are removed: p1, p2 Then no dependency pair remains.