YES We show the termination of the TRS R: g(x,|0|()) -> |0|() g(d(),s(x)) -> s(s(g(d(),x))) g(h(),s(|0|())) -> |0|() g(h(),s(s(x))) -> s(g(h(),x)) double(x) -> g(d(),x) half(x) -> g(h(),x) f(s(x),y) -> f(half(s(x)),double(y)) f(s(|0|()),y) -> y id(x) -> f(x,s(|0|())) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: g#(d(),s(x)) -> g#(d(),x) p2: g#(h(),s(s(x))) -> g#(h(),x) p3: double#(x) -> g#(d(),x) p4: half#(x) -> g#(h(),x) p5: f#(s(x),y) -> f#(half(s(x)),double(y)) p6: f#(s(x),y) -> half#(s(x)) p7: f#(s(x),y) -> double#(y) p8: id#(x) -> f#(x,s(|0|())) and R consists of: r1: g(x,|0|()) -> |0|() r2: g(d(),s(x)) -> s(s(g(d(),x))) r3: g(h(),s(|0|())) -> |0|() r4: g(h(),s(s(x))) -> s(g(h(),x)) r5: double(x) -> g(d(),x) r6: half(x) -> g(h(),x) r7: f(s(x),y) -> f(half(s(x)),double(y)) r8: f(s(|0|()),y) -> y r9: id(x) -> f(x,s(|0|())) The estimated dependency graph contains the following SCCs: {p5} {p1} {p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: f#(s(x),y) -> f#(half(s(x)),double(y)) and R consists of: r1: g(x,|0|()) -> |0|() r2: g(d(),s(x)) -> s(s(g(d(),x))) r3: g(h(),s(|0|())) -> |0|() r4: g(h(),s(s(x))) -> s(g(h(),x)) r5: double(x) -> g(d(),x) r6: half(x) -> g(h(),x) r7: f(s(x),y) -> f(half(s(x)),double(y)) r8: f(s(|0|()),y) -> y r9: id(x) -> f(x,s(|0|())) The set of usable rules consists of r1, r3, r4, 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: f#_A(x1,x2) = 0 s_A(x1) = 3 half_A(x1) = 3 double_A(x1) = 1 g_A(x1,x2) = x1 + 1 |0|_A() = 1 h_A() = 2 f#!_A(x1,x2) = 5 s!_A(x1) = x1 + 5 half!_A(x1) = 4 double!_A(x1) = 3 g!_A(x1,x2) = 2 |0|!_A() = 0 h!_A() = 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: f#_A(x1,x2) = max{0, x1 - 22} s_A(x1) = x1 + 21 half_A(x1) = max{4, x1 - 17} double_A(x1) = 32 g_A(x1,x2) = max{4, x1 - 35, x2 - 17} |0|_A = 1 h_A = 27 f#!_A(x1,x2) = max{2, x1 - 5} s!_A(x1) = x1 + 5 half!_A(x1) = 1 double!_A(x1) = 0 g!_A(x1,x2) = max{6, x1 - 1} |0|!_A = 27 h!_A = 1 partial status: pi(f#) = [] pi(s) = [] pi(half) = [1] pi(double) = [1] pi(g) = [1, 2] pi(|0|) = [] pi(h) = [] 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: g#(d(),s(x)) -> g#(d(),x) and R consists of: r1: g(x,|0|()) -> |0|() r2: g(d(),s(x)) -> s(s(g(d(),x))) r3: g(h(),s(|0|())) -> |0|() r4: g(h(),s(s(x))) -> s(g(h(),x)) r5: double(x) -> g(d(),x) r6: half(x) -> g(h(),x) r7: f(s(x),y) -> f(half(s(x)),double(y)) r8: f(s(|0|()),y) -> y r9: id(x) -> f(x,s(|0|())) 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: g#_A(x1,x2) = x2 d_A() = 1 s_A(x1) = x1 + 3 g#!_A(x1,x2) = 4 d!_A() = 3 s!_A(x1) = 4 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: g#_A(x1,x2) = 0 d_A = 0 s_A(x1) = max{20, x1 - 21} g#!_A(x1,x2) = 5 d!_A = 4 s!_A(x1) = x1 + 5 partial status: pi(g#) = [2] pi(d) = [] pi(s) = [1] 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: g#(h(),s(s(x))) -> g#(h(),x) and R consists of: r1: g(x,|0|()) -> |0|() r2: g(d(),s(x)) -> s(s(g(d(),x))) r3: g(h(),s(|0|())) -> |0|() r4: g(h(),s(s(x))) -> s(g(h(),x)) r5: double(x) -> g(d(),x) r6: half(x) -> g(h(),x) r7: f(s(x),y) -> f(half(s(x)),double(y)) r8: f(s(|0|()),y) -> y r9: id(x) -> f(x,s(|0|())) 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: g#_A(x1,x2) = 0 h_A() = 1 s_A(x1) = 5 g#!_A(x1,x2) = 2 h!_A() = 4 s!_A(x1) = x1 + 3 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: g#_A(x1,x2) = 0 h_A = 2 s_A(x1) = max{34, x1 - 20} g#!_A(x1,x2) = 0 h!_A = 118 s!_A(x1) = max{98, x1 + 8} partial status: pi(g#) = [2] pi(h) = [] pi(s) = [1] The following rules are removed: p1 Then no dependency pair remains.