YES We show the termination of the TRS R: +(x,|0|()) -> x +(|0|(),x) -> x +(s(x),s(y)) -> s(s(+(x,y))) *(x,|0|()) -> |0|() *(|0|(),x) -> |0|() *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) 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: *#(s(x),s(y)) -> +#(*(x,y),+(x,y)) p3: *#(s(x),s(y)) -> *#(x,y) p4: *#(s(x),s(y)) -> +#(x,y) p5: sum#(cons(x,l)) -> +#(x,sum(l)) p6: sum#(cons(x,l)) -> sum#(l) p7: prod#(cons(x,l)) -> *#(x,prod(l)) p8: 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,|0|()) -> |0|() r5: *(|0|(),x) -> |0|() r6: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r7: sum(nil()) -> |0|() r8: sum(cons(x,l)) -> +(x,sum(l)) r9: prod(nil()) -> s(|0|()) r10: prod(cons(x,l)) -> *(x,prod(l)) The estimated dependency graph contains the following SCCs: {p6} {p8} {p3} {p1} -- 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,|0|()) -> |0|() r5: *(|0|(),x) -> |0|() r6: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r7: sum(nil()) -> |0|() r8: sum(cons(x,l)) -> +(x,sum(l)) r9: prod(nil()) -> s(|0|()) r10: 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: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: sum#_A(x1) = x1 cons_A(x1,x2) = x2 + 5 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: sum#_A(x1) = x1 cons_A(x1,x2) = max{x1 - 1, x2} sum#!_A(x1) = max{1, x1 - 41} cons!_A(x1,x2) = max{3, x1 - 40, x2 - 40} 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,|0|()) -> |0|() r5: *(|0|(),x) -> |0|() r6: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r7: sum(nil()) -> |0|() r8: sum(cons(x,l)) -> +(x,sum(l)) r9: prod(nil()) -> s(|0|()) r10: prod(cons(x,l)) -> *(x,prod(l)) The set of usable rules consists of r5 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: prod#_A(x1) = x1 cons_A(x1,x2) = x2 + 4 *_A(x1,x2) = 3 |0|_A() = 1 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: prod#_A(x1) = x1 cons_A(x1,x2) = max{x1 - 1, x2 + 1} *_A(x1,x2) = max{52, x1 - 51, x2 - 51} |0|_A = 4 prod#!_A(x1) = max{1, x1 - 74} cons!_A(x1,x2) = max{3, x1 - 4, x2 - 73} *!_A(x1,x2) = max{2, x1 - 5, x2 - 7} |0|!_A = 1 partial status: pi(prod#) = [] pi(cons) = [2] pi(*) = [] pi(|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: *#(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,|0|()) -> |0|() r5: *(|0|(),x) -> |0|() r6: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r7: sum(nil()) -> |0|() r8: sum(cons(x,l)) -> +(x,sum(l)) r9: prod(nil()) -> s(|0|()) r10: 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: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: *#_A(x1,x2) = 0 s_A(x1) = 3 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: *#_A(x1,x2) = max{x1, x2} s_A(x1) = x1 + 13 *#!_A(x1,x2) = max{8, x1 - 1, x2 - 47} s!_A(x1) = max{7, x1 - 48} partial status: pi(*#) = [] pi(s) = [] 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: +#(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,|0|()) -> |0|() r5: *(|0|(),x) -> |0|() r6: *(s(x),s(y)) -> s(+(*(x,y),+(x,y))) r7: sum(nil()) -> |0|() r8: sum(cons(x,l)) -> +(x,sum(l)) r9: prod(nil()) -> s(|0|()) r10: prod(cons(x,l)) -> *(x,prod(l)) The set of usable rules consists of r5 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: +#_A(x1,x2) = 0 s_A(x1) = 3 *_A(x1,x2) = 2 |0|_A() = 1 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: +#_A(x1,x2) = 0 s_A(x1) = max{14, x1 + 4} *_A(x1,x2) = max{10, x1 - 16, x2 - 37} |0|_A = 5 +#!_A(x1,x2) = max{1, x2 - 2} s!_A(x1) = max{0, x1 - 43} *!_A(x1,x2) = max{1, x1 - 79} |0|!_A = 2 partial status: pi(+#) = [] pi(s) = [] pi(*) = [] pi(|0|) = [] The following rules are removed: p1 Then no dependency pair remains.