YES We show the termination of the TRS R: active(f(X)) -> mark(g(h(f(X)))) mark(f(X)) -> active(f(mark(X))) mark(g(X)) -> active(g(X)) mark(h(X)) -> active(h(mark(X))) f(mark(X)) -> f(X) f(active(X)) -> f(X) g(mark(X)) -> g(X) g(active(X)) -> g(X) h(mark(X)) -> h(X) h(active(X)) -> h(X) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: active#(f(X)) -> mark#(g(h(f(X)))) p2: active#(f(X)) -> g#(h(f(X))) p3: active#(f(X)) -> h#(f(X)) p4: mark#(f(X)) -> active#(f(mark(X))) p5: mark#(f(X)) -> f#(mark(X)) p6: mark#(f(X)) -> mark#(X) p7: mark#(g(X)) -> active#(g(X)) p8: mark#(h(X)) -> active#(h(mark(X))) p9: mark#(h(X)) -> h#(mark(X)) p10: mark#(h(X)) -> mark#(X) p11: f#(mark(X)) -> f#(X) p12: f#(active(X)) -> f#(X) p13: g#(mark(X)) -> g#(X) p14: g#(active(X)) -> g#(X) p15: h#(mark(X)) -> h#(X) p16: h#(active(X)) -> h#(X) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(X) The estimated dependency graph contains the following SCCs: {p1, p4, p6, p7, p8, p10} {p13, p14} {p15, p16} {p11, p12} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: active#(f(X)) -> mark#(g(h(f(X)))) p2: mark#(h(X)) -> mark#(X) p3: mark#(h(X)) -> active#(h(mark(X))) p4: mark#(g(X)) -> active#(g(X)) p5: mark#(f(X)) -> mark#(X) p6: mark#(f(X)) -> active#(f(mark(X))) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(X) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: active#_A(x1) = max{7, x1 - 10} f_A(x1) = x1 + 18 mark#_A(x1) = max{1, x1 - 4} g_A(x1) = max{12, x1 - 26} h_A(x1) = x1 + 19 mark_A(x1) = x1 + 5 active_A(x1) = x1 precedence: active# = f = mark# = g = h = mark = active partial status: pi(active#) = [] pi(f) = [] pi(mark#) = [] pi(g) = [] pi(h) = [] pi(mark) = [] pi(active) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: active#_A(x1) = 31 f_A(x1) = 30 mark#_A(x1) = 30 g_A(x1) = 29 h_A(x1) = 51 mark_A(x1) = max{12, x1 + 5} active_A(x1) = max{13, x1 + 2} precedence: h > f = mark = active > g > mark# > active# partial status: pi(active#) = [] pi(f) = [] pi(mark#) = [] pi(g) = [] pi(h) = [] pi(mark) = [1] pi(active) = [1] The next rules are strictly ordered: p1, p3, p4, p6 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: mark#(h(X)) -> mark#(X) p2: mark#(f(X)) -> mark#(X) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(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: mark#(h(X)) -> mark#(X) p2: mark#(f(X)) -> mark#(X) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(X) The set of usable rules consists of (no rules) Take the monotone reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: mark#_A(x1) = max{6, x1 + 4} h_A(x1) = max{4, x1 + 3} f_A(x1) = max{2, x1 + 1} precedence: mark# = h = f partial status: pi(mark#) = [1] pi(h) = [1] pi(f) = [1] 2. weighted path order base order: max/plus interpretations on natural numbers: mark#_A(x1) = x1 + 1 h_A(x1) = x1 f_A(x1) = x1 precedence: mark# = h = f partial status: pi(mark#) = [1] pi(h) = [1] pi(f) = [1] The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: g#(mark(X)) -> g#(X) p2: g#(active(X)) -> g#(X) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(X) The set of usable rules consists of (no rules) Take the monotone reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: g#_A(x1) = x1 + 2 mark_A(x1) = x1 active_A(x1) = x1 + 2 precedence: mark > active > g# partial status: pi(g#) = [1] pi(mark) = [1] pi(active) = [1] 2. weighted path order base order: max/plus interpretations on natural numbers: g#_A(x1) = x1 + 1 mark_A(x1) = x1 active_A(x1) = x1 precedence: g# = mark = active partial status: pi(g#) = [1] pi(mark) = [1] pi(active) = [1] The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: h#(mark(X)) -> h#(X) p2: h#(active(X)) -> h#(X) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(X) The set of usable rules consists of (no rules) Take the monotone reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: h#_A(x1) = x1 + 2 mark_A(x1) = x1 active_A(x1) = x1 + 2 precedence: mark > active > h# partial status: pi(h#) = [1] pi(mark) = [1] pi(active) = [1] 2. weighted path order base order: max/plus interpretations on natural numbers: h#_A(x1) = x1 + 1 mark_A(x1) = x1 active_A(x1) = x1 precedence: h# = mark = active partial status: pi(h#) = [1] pi(mark) = [1] pi(active) = [1] The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: f#(mark(X)) -> f#(X) p2: f#(active(X)) -> f#(X) and R consists of: r1: active(f(X)) -> mark(g(h(f(X)))) r2: mark(f(X)) -> active(f(mark(X))) r3: mark(g(X)) -> active(g(X)) r4: mark(h(X)) -> active(h(mark(X))) r5: f(mark(X)) -> f(X) r6: f(active(X)) -> f(X) r7: g(mark(X)) -> g(X) r8: g(active(X)) -> g(X) r9: h(mark(X)) -> h(X) r10: h(active(X)) -> h(X) The set of usable rules consists of (no rules) Take the monotone reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: f#_A(x1) = x1 + 2 mark_A(x1) = x1 active_A(x1) = x1 + 2 precedence: mark > active > f# partial status: pi(f#) = [1] pi(mark) = [1] pi(active) = [1] 2. weighted path order base order: max/plus interpretations on natural numbers: f#_A(x1) = x1 + 1 mark_A(x1) = x1 active_A(x1) = x1 precedence: f# = mark = active partial status: pi(f#) = [1] pi(mark) = [1] pi(active) = [1] The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains.