YES We show the termination of the TRS R: active(f(x)) -> mark(x) top(active(c())) -> top(mark(c())) top(mark(x)) -> top(check(x)) check(f(x)) -> f(check(x)) check(x) -> start(match(f(X()),x)) match(f(x),f(y)) -> f(match(x,y)) match(X(),x) -> proper(x) proper(c()) -> ok(c()) proper(f(x)) -> f(proper(x)) f(ok(x)) -> ok(f(x)) start(ok(x)) -> found(x) f(found(x)) -> found(f(x)) top(found(x)) -> top(active(x)) active(f(x)) -> f(active(x)) f(mark(x)) -> mark(f(x)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: top#(active(c())) -> top#(mark(c())) p2: top#(mark(x)) -> top#(check(x)) p3: top#(mark(x)) -> check#(x) p4: check#(f(x)) -> f#(check(x)) p5: check#(f(x)) -> check#(x) p6: check#(x) -> start#(match(f(X()),x)) p7: check#(x) -> match#(f(X()),x) p8: check#(x) -> f#(X()) p9: match#(f(x),f(y)) -> f#(match(x,y)) p10: match#(f(x),f(y)) -> match#(x,y) p11: match#(X(),x) -> proper#(x) p12: proper#(f(x)) -> f#(proper(x)) p13: proper#(f(x)) -> proper#(x) p14: f#(ok(x)) -> f#(x) p15: f#(found(x)) -> f#(x) p16: top#(found(x)) -> top#(active(x)) p17: top#(found(x)) -> active#(x) p18: active#(f(x)) -> f#(active(x)) p19: active#(f(x)) -> active#(x) p20: f#(mark(x)) -> f#(x) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) The estimated dependency graph contains the following SCCs: {p1, p2, p16} {p5} {p19} {p10} {p13} {p14, p15, p20} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: top#(active(c())) -> top#(mark(c())) p2: top#(mark(x)) -> top#(check(x)) p3: top#(found(x)) -> top#(active(x)) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) The set of usable rules consists of r1, r4, r5, r6, r7, r8, r9, r10, r11, r12, r14, r15 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!): max/plus interpretation on natural numbers: top#_A(x1) = max{27, x1 - 25} active_A(x1) = max{22, x1 - 1} c_A = 25 mark_A(x1) = max{20, x1 - 2} check_A(x1) = 52 found_A(x1) = max{45, x1 + 26} f_A(x1) = max{19, x1} start_A(x1) = x1 + 27 match_A(x1,x2) = x1 + 1 X_A = 24 proper_A(x1) = 25 ok_A(x1) = max{18, x1} top#!_A(x1) = max{69, x1 + 17} active!_A(x1) = x1 + 10 c!_A = 38 mark!_A(x1) = 8 check!_A(x1) = max{14, x1 + 12} found!_A(x1) = 10 f!_A(x1) = 14 start!_A(x1) = max{11, x1 - 12} match!_A(x1,x2) = max{11, x1 - 1} X!_A = 15 proper!_A(x1) = 14 ok!_A(x1) = max{15, x1 - 26} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: top#_A(x1) = 0 active_A(x1) = max{16, x1 - 18} c_A = 36 mark_A(x1) = 16 check_A(x1) = 16 found_A(x1) = max{16, x1 - 12} f_A(x1) = max{16, x1 - 17} start_A(x1) = max{16, x1 - 12} match_A(x1,x2) = max{15, x1 + 12} X_A = 24 proper_A(x1) = 36 ok_A(x1) = max{16, x1} top#!_A(x1) = x1 + 14 active!_A(x1) = 0 c!_A = 4 mark!_A(x1) = 0 check!_A(x1) = 0 found!_A(x1) = 2 f!_A(x1) = max{11, x1 - 25} start!_A(x1) = 0 match!_A(x1,x2) = 0 X!_A = 1 proper!_A(x1) = 11 ok!_A(x1) = 3 partial status: pi(top#) = [] pi(active) = [1] pi(c) = [] pi(mark) = [] pi(check) = [1] pi(found) = [] pi(f) = [1] pi(start) = [] pi(match) = [2] pi(X) = [] pi(proper) = [1] pi(ok) = [] The following rules are removed: p1 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: top#(mark(x)) -> top#(check(x)) p2: top#(found(x)) -> top#(active(x)) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: top#(mark(x)) -> top#(check(x)) p2: top#(found(x)) -> top#(active(x)) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) The set of usable rules consists of r1, r4, r5, r6, r7, r8, r9, r10, r11, r12, r14, r15 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!): max/plus interpretation on natural numbers: top#_A(x1) = 0 mark_A(x1) = 19 check_A(x1) = x1 + 42 found_A(x1) = 24 active_A(x1) = x1 + 23 f_A(x1) = max{25, x1 - 22} start_A(x1) = max{42, x1 - 12} match_A(x1,x2) = max{x1 - 86, x2 + 23} X_A = 111 proper_A(x1) = 25 c_A = 66 ok_A(x1) = 13 top#!_A(x1) = 0 mark!_A(x1) = 1 check!_A(x1) = x1 + 51 found!_A(x1) = 9 active!_A(x1) = x1 + 32 f!_A(x1) = max{6, x1 - 14} start!_A(x1) = max{3, x1 - 4} match!_A(x1,x2) = max{75, x1 - 37, x2 + 32} X!_A = 50 proper!_A(x1) = max{75, x1 + 23} c!_A = 2 ok!_A(x1) = 2 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: top#_A(x1) = max{0, x1 - 10} mark_A(x1) = max{53, x1 + 24} check_A(x1) = x1 + 23 found_A(x1) = max{23, x1 + 9} active_A(x1) = max{4, x1 + 1} f_A(x1) = max{52, x1 + 39} start_A(x1) = max{23, x1 - 3} match_A(x1,x2) = x2 + 26 X_A = 13 proper_A(x1) = max{13, x1 + 12} c_A = 16 ok_A(x1) = max{25, x1 + 12} top#!_A(x1) = max{3, x1} mark!_A(x1) = 3 check!_A(x1) = max{69, x1 + 15} found!_A(x1) = max{3, x1 - 53} active!_A(x1) = max{69, x1 - 54} f!_A(x1) = 68 start!_A(x1) = max{16, x1 - 26} match!_A(x1,x2) = max{70, x1 - 38, x2 - 53} X!_A = 50 proper!_A(x1) = max{49, x1 - 54} c!_A = 49 ok!_A(x1) = 0 partial status: pi(top#) = [] pi(mark) = [] pi(check) = [1] pi(found) = [] pi(active) = [] pi(f) = [] pi(start) = [] pi(match) = [1] pi(X) = [] pi(proper) = [] pi(c) = [] pi(ok) = [] The following rules are removed: p1, p2 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: check#(f(x)) -> check#(x) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) 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!): max/plus interpretation on natural numbers: check#_A(x1) = 0 f_A(x1) = max{7, x1 - 21} check#!_A(x1) = max{4, x1 - 41} f!_A(x1) = max{4, x1 - 41} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: check#_A(x1) = 0 f_A(x1) = max{9, x1 - 15} check#!_A(x1) = max{1, x1 - 45} f!_A(x1) = max{5, x1 - 45} partial status: pi(check#) = [1] pi(f) = [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: active#(f(x)) -> active#(x) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) 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!): max/plus interpretation on natural numbers: active#_A(x1) = 0 f_A(x1) = max{6, x1 - 15} active#!_A(x1) = max{2, x1 - 34} f!_A(x1) = max{2, x1 - 34} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: active#_A(x1) = 0 f_A(x1) = max{7, x1 - 20} active#!_A(x1) = max{2, x1 - 67} f!_A(x1) = max{2, x1 - 66} partial status: pi(active#) = [1] pi(f) = [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: match#(f(x),f(y)) -> match#(x,y) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) 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!): max/plus interpretation on natural numbers: match#_A(x1,x2) = 0 f_A(x1) = max{7, x1 - 18} match#!_A(x1,x2) = max{0, x2 - 41} f!_A(x1) = max{2, x1 - 40} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: match#_A(x1,x2) = 0 f_A(x1) = max{7, x1 - 11} match#!_A(x1,x2) = max{3, x1 - 39, x2 - 8} f!_A(x1) = max{2, x1 - 38} partial status: pi(match#) = [2] pi(f) = [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: proper#(f(x)) -> proper#(x) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) 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!): max/plus interpretation on natural numbers: proper#_A(x1) = 0 f_A(x1) = max{6, x1 - 15} proper#!_A(x1) = max{2, x1 - 55} f!_A(x1) = max{2, x1 - 55} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: proper#_A(x1) = 0 f_A(x1) = max{7, x1 - 12} proper#!_A(x1) = max{2, x1 - 64} f!_A(x1) = max{2, x1 - 63} partial status: pi(proper#) = [1] pi(f) = [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: f#(ok(x)) -> f#(x) p2: f#(mark(x)) -> f#(x) p3: f#(found(x)) -> f#(x) and R consists of: r1: active(f(x)) -> mark(x) r2: top(active(c())) -> top(mark(c())) r3: top(mark(x)) -> top(check(x)) r4: check(f(x)) -> f(check(x)) r5: check(x) -> start(match(f(X()),x)) r6: match(f(x),f(y)) -> f(match(x,y)) r7: match(X(),x) -> proper(x) r8: proper(c()) -> ok(c()) r9: proper(f(x)) -> f(proper(x)) r10: f(ok(x)) -> ok(f(x)) r11: start(ok(x)) -> found(x) r12: f(found(x)) -> found(f(x)) r13: top(found(x)) -> top(active(x)) r14: active(f(x)) -> f(active(x)) r15: f(mark(x)) -> mark(f(x)) 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!): max/plus interpretation on natural numbers: f#_A(x1) = 0 ok_A(x1) = max{4, x1 - 7} mark_A(x1) = max{4, x1 - 12} found_A(x1) = max{7, x1 - 7} f#!_A(x1) = 14 ok!_A(x1) = max{3, x1 - 40} mark!_A(x1) = max{7, x1 - 44} found!_A(x1) = max{13, x1 - 39} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: f#_A(x1) = 0 ok_A(x1) = max{13, x1 - 12} mark_A(x1) = max{12, x1 - 13} found_A(x1) = max{3, x1 - 22} f#!_A(x1) = 0 ok!_A(x1) = max{3, x1 - 49} mark!_A(x1) = max{1, x1 - 51} found!_A(x1) = max{5, x1 - 25} partial status: pi(f#) = [1] pi(ok) = [1] pi(mark) = [1] pi(found) = [1] The following rules are removed: p1, p2, p3 Then no dependency pair remains.