YES We show the termination of the TRS R: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) mark(f(X1,X2)) -> a__f(mark(X1),X2) mark(g(X)) -> g(mark(X)) a__f(X1,X2) -> f(X1,X2) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(g(X),Y) -> a__f#(mark(X),f(g(X),Y)) p2: a__f#(g(X),Y) -> mark#(X) p3: mark#(f(X1,X2)) -> a__f#(mark(X1),X2) p4: mark#(f(X1,X2)) -> mark#(X1) p5: mark#(g(X)) -> mark#(X) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(g(X),Y) -> a__f#(mark(X),f(g(X),Y)) p2: a__f#(g(X),Y) -> mark#(X) p3: mark#(g(X)) -> mark#(X) p4: mark#(f(X1,X2)) -> mark#(X1) p5: mark#(f(X1,X2)) -> a__f#(mark(X1),X2) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The set of usable rules consists of r1, r2, r3, r4 Take the reduction pair: weighted path order base order: max/plus interpretations on natural numbers: a__f#_A(x1,x2) = max{8, x1 + 5, x2 - 3} g_A(x1) = x1 + 10 mark_A(x1) = x1 + 6 f_A(x1,x2) = max{x1 + 7, x2 - 5} mark#_A(x1) = x1 + 4 a__f_A(x1,x2) = max{8, x1 + 7, x2 - 5} precedence: a__f# = g = mark = f = mark# = a__f partial status: pi(a__f#) = [] pi(g) = [1] pi(mark) = [1] pi(f) = [1] pi(mark#) = [1] pi(a__f) = [1] The next rules are strictly ordered: p3 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(g(X),Y) -> a__f#(mark(X),f(g(X),Y)) p2: a__f#(g(X),Y) -> mark#(X) p3: mark#(f(X1,X2)) -> mark#(X1) p4: mark#(f(X1,X2)) -> a__f#(mark(X1),X2) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(g(X),Y) -> a__f#(mark(X),f(g(X),Y)) p2: a__f#(g(X),Y) -> mark#(X) p3: mark#(f(X1,X2)) -> a__f#(mark(X1),X2) p4: mark#(f(X1,X2)) -> mark#(X1) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The set of usable rules consists of r1, r2, r3, r4 Take the reduction pair: weighted path order base order: max/plus interpretations on natural numbers: a__f#_A(x1,x2) = max{x1 + 5, x2 + 4} g_A(x1) = x1 mark_A(x1) = x1 f_A(x1,x2) = max{x1 + 1, x2} mark#_A(x1) = x1 + 4 a__f_A(x1,x2) = max{x1 + 1, x2} precedence: a__f# = g = mark = f = mark# = a__f partial status: pi(a__f#) = [] pi(g) = [1] pi(mark) = [1] pi(f) = [] pi(mark#) = [1] pi(a__f) = [] The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(g(X),Y) -> a__f#(mark(X),f(g(X),Y)) p2: mark#(f(X1,X2)) -> a__f#(mark(X1),X2) p3: mark#(f(X1,X2)) -> mark#(X1) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The estimated dependency graph contains the following SCCs: {p3} {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(f(X1,X2)) -> mark#(X1) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The set of usable rules consists of (no rules) Take the reduction pair: weighted path order base order: max/plus interpretations on natural numbers: mark#_A(x1) = x1 + 2 f_A(x1,x2) = max{x1 + 1, x2 + 1} precedence: mark# = f partial status: pi(mark#) = [] pi(f) = [2] The next rules are strictly ordered: p1 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: a__f#(g(X),Y) -> a__f#(mark(X),f(g(X),Y)) and R consists of: r1: a__f(g(X),Y) -> a__f(mark(X),f(g(X),Y)) r2: mark(f(X1,X2)) -> a__f(mark(X1),X2) r3: mark(g(X)) -> g(mark(X)) r4: a__f(X1,X2) -> f(X1,X2) The set of usable rules consists of r1, r2, r3, r4 Take the reduction pair: weighted path order base order: max/plus interpretations on natural numbers: a__f#_A(x1,x2) = max{11, x1 + 6} g_A(x1) = x1 + 11 mark_A(x1) = x1 + 7 f_A(x1,x2) = max{x1 + 8, x2} a__f_A(x1,x2) = max{9, x1 + 8, x2} precedence: a__f# = g = mark = f = a__f partial status: pi(a__f#) = [] pi(g) = [1] pi(mark) = [1] pi(f) = [1] pi(a__f) = [1] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.