YES We show the termination of the TRS R: active(f(x)) -> mark(f(f(x))) chk(no(f(x))) -> f(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) mat(f(x),f(y())) -> f(mat(x,y())) chk(no(c())) -> active(c()) mat(f(x),c()) -> no(c()) f(active(x)) -> active(f(x)) f(no(x)) -> no(f(x)) f(mark(x)) -> mark(f(x)) tp(mark(x)) -> tp(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: active#(f(x)) -> f#(f(x)) p2: chk#(no(f(x))) -> f#(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) p3: chk#(no(f(x))) -> chk#(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x)) p4: chk#(no(f(x))) -> mat#(f(f(f(f(f(f(f(f(f(f(X())))))))))),x) p5: chk#(no(f(x))) -> f#(f(f(f(f(f(f(f(f(f(X())))))))))) p6: chk#(no(f(x))) -> f#(f(f(f(f(f(f(f(f(X()))))))))) p7: chk#(no(f(x))) -> f#(f(f(f(f(f(f(f(X())))))))) p8: chk#(no(f(x))) -> f#(f(f(f(f(f(f(X()))))))) p9: chk#(no(f(x))) -> f#(f(f(f(f(f(X())))))) p10: chk#(no(f(x))) -> f#(f(f(f(f(X()))))) p11: chk#(no(f(x))) -> f#(f(f(f(X())))) p12: chk#(no(f(x))) -> f#(f(f(X()))) p13: chk#(no(f(x))) -> f#(f(X())) p14: chk#(no(f(x))) -> f#(X()) p15: mat#(f(x),f(y())) -> f#(mat(x,y())) p16: mat#(f(x),f(y())) -> mat#(x,y()) p17: chk#(no(c())) -> active#(c()) p18: f#(active(x)) -> active#(f(x)) p19: f#(active(x)) -> f#(x) p20: f#(no(x)) -> f#(x) p21: f#(mark(x)) -> f#(x) p22: tp#(mark(x)) -> tp#(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) p23: tp#(mark(x)) -> chk#(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x)) p24: tp#(mark(x)) -> mat#(f(f(f(f(f(f(f(f(f(f(X())))))))))),x) p25: tp#(mark(x)) -> f#(f(f(f(f(f(f(f(f(f(X())))))))))) p26: tp#(mark(x)) -> f#(f(f(f(f(f(f(f(f(X()))))))))) p27: tp#(mark(x)) -> f#(f(f(f(f(f(f(f(X())))))))) p28: tp#(mark(x)) -> f#(f(f(f(f(f(f(X()))))))) p29: tp#(mark(x)) -> f#(f(f(f(f(f(X())))))) p30: tp#(mark(x)) -> f#(f(f(f(f(X()))))) p31: tp#(mark(x)) -> f#(f(f(f(X())))) p32: tp#(mark(x)) -> f#(f(f(X()))) p33: tp#(mark(x)) -> f#(f(X())) p34: tp#(mark(x)) -> f#(X()) and R consists of: r1: active(f(x)) -> mark(f(f(x))) r2: chk(no(f(x))) -> f(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) r3: mat(f(x),f(y())) -> f(mat(x,y())) r4: chk(no(c())) -> active(c()) r5: mat(f(x),c()) -> no(c()) r6: f(active(x)) -> active(f(x)) r7: f(no(x)) -> no(f(x)) r8: f(mark(x)) -> mark(f(x)) r9: tp(mark(x)) -> tp(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) The estimated dependency graph contains the following SCCs: {p22} {p3} {p1, p18, p19, p20, p21} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: tp#(mark(x)) -> tp#(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) and R consists of: r1: active(f(x)) -> mark(f(f(x))) r2: chk(no(f(x))) -> f(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) r3: mat(f(x),f(y())) -> f(mat(x,y())) r4: chk(no(c())) -> active(c()) r5: mat(f(x),c()) -> no(c()) r6: f(active(x)) -> active(f(x)) r7: f(no(x)) -> no(f(x)) r8: f(mark(x)) -> mark(f(x)) r9: tp(mark(x)) -> tp(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 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: tp#_A(x1) = 0 mark_A(x1) = 5 chk_A(x1) = x1 mat_A(x1,x2) = x2 f_A(x1) = 7 X_A() = 7 active_A(x1) = 5 no_A(x1) = x1 y_A() = 1 c_A() = 15 tp_A(x1) = 0 tp#!_A(x1) = 0 mark!_A(x1) = x1 + 7 chk!_A(x1) = x1 + 1 mat!_A(x1,x2) = x2 + 6 f!_A(x1) = x1 + 10 X!_A() = 8 active!_A(x1) = 15 no!_A(x1) = 9 y!_A() = 12 c!_A() = 17 tp!_A(x1) = 17 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: tp#_A(x1) = 0 mark_A(x1) = 0 chk_A(x1) = 0 mat_A(x1,x2) = 2 f_A(x1) = x1 X_A() = 3 active_A(x1) = 0 no_A(x1) = x1 + 1 y_A() = 3 c_A() = 1 tp_A(x1) = 0 tp#!_A(x1) = 2 mark!_A(x1) = 6 chk!_A(x1) = x1 + 2 mat!_A(x1,x2) = 1 f!_A(x1) = x1 + 7 X!_A() = 3 active!_A(x1) = 5 no!_A(x1) = x1 + 9 y!_A() = 0 c!_A() = 10 tp!_A(x1) = 11 partial status: pi(tp#) = [1] pi(mark) = [] pi(chk) = [1] pi(mat) = [] pi(f) = [] pi(X) = [] pi(active) = [] pi(no) = [1] pi(y) = [] pi(c) = [] pi(tp) = [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: chk#(no(f(x))) -> chk#(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x)) and R consists of: r1: active(f(x)) -> mark(f(f(x))) r2: chk(no(f(x))) -> f(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) r3: mat(f(x),f(y())) -> f(mat(x,y())) r4: chk(no(c())) -> active(c()) r5: mat(f(x),c()) -> no(c()) r6: f(active(x)) -> active(f(x)) r7: f(no(x)) -> no(f(x)) r8: f(mark(x)) -> mark(f(x)) r9: tp(mark(x)) -> tp(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) The set of usable rules consists of r3, r5 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: chk#_A(x1) = x1 no_A(x1) = x1 + 1 f_A(x1) = x1 + 2 mat_A(x1,x2) = x2 + 2 X_A() = 1 y_A() = 1 c_A() = 1 chk#!_A(x1) = x1 + 2 no!_A(x1) = 3 f!_A(x1) = 1 mat!_A(x1,x2) = x2 + 6 X!_A() = 0 y!_A() = 2 c!_A() = 0 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: chk#_A(x1) = x1 no_A(x1) = x1 + 1 f_A(x1) = x1 + 2 mat_A(x1,x2) = x2 + 2 X_A() = 1 y_A() = 1 c_A() = 1 chk#!_A(x1) = 3 no!_A(x1) = 4 f!_A(x1) = 2 mat!_A(x1,x2) = 1 X!_A() = 1 y!_A() = 3 c!_A() = 0 partial status: pi(chk#) = [] pi(no) = [1] pi(f) = [] pi(mat) = [1, 2] pi(X) = [] pi(y) = [] pi(c) = [] 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: active#(f(x)) -> f#(f(x)) p2: f#(mark(x)) -> f#(x) p3: f#(no(x)) -> f#(x) p4: f#(active(x)) -> f#(x) p5: f#(active(x)) -> active#(f(x)) and R consists of: r1: active(f(x)) -> mark(f(f(x))) r2: chk(no(f(x))) -> f(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) r3: mat(f(x),f(y())) -> f(mat(x,y())) r4: chk(no(c())) -> active(c()) r5: mat(f(x),c()) -> no(c()) r6: f(active(x)) -> active(f(x)) r7: f(no(x)) -> no(f(x)) r8: f(mark(x)) -> mark(f(x)) r9: tp(mark(x)) -> tp(chk(mat(f(f(f(f(f(f(f(f(f(f(X())))))))))),x))) The set of usable rules consists of r1, r6, r7, r8 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: active#_A(x1) = 0 f_A(x1) = x1 + 2 f#_A(x1) = 0 mark_A(x1) = x1 + 24 no_A(x1) = 28 active_A(x1) = x1 + 53 active#!_A(x1) = 0 f!_A(x1) = x1 + 1 f#!_A(x1) = 0 mark!_A(x1) = x1 + 22 no!_A(x1) = 28 active!_A(x1) = x1 + 25 2. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: active#_A(x1) = 0 f_A(x1) = x1 + 3 f#_A(x1) = 0 mark_A(x1) = x1 + 36 no_A(x1) = x1 + 29 active_A(x1) = x1 + 40 active#!_A(x1) = x1 + 1 f!_A(x1) = x1 + 5 f#!_A(x1) = x1 mark!_A(x1) = x1 + 37 no!_A(x1) = 33 active!_A(x1) = x1 + 41 partial status: pi(active#) = [] pi(f) = [] pi(f#) = [] pi(mark) = [] pi(no) = [] pi(active) = [] The following rules are removed: p1, p2, p3, p4, p5 Then no dependency pair remains.