YES We show the termination of the TRS R: pred(s(x)) -> x minus(x,|0|()) -> x minus(x,s(y)) -> pred(minus(x,y)) quot(|0|(),s(y)) -> |0|() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: minus#(x,s(y)) -> pred#(minus(x,y)) p2: minus#(x,s(y)) -> minus#(x,y) p3: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) p4: quot#(s(x),s(y)) -> minus#(x,y) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) The estimated dependency graph contains the following SCCs: {p3} {p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) The set of usable rules consists of r1, r2, r3 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: quot#_A(x1,x2) = max{0, x1 - 11, x2 - 14} s_A(x1) = x1 + 10 minus_A(x1,x2) = max{x1 + 10, x2 - 12} pred_A(x1) = max{8, x1 - 9} |0|_A = 22 quot#!_A(x1,x2) = max{0, x2 - 5} s!_A(x1) = max{1, x1 - 4} minus!_A(x1,x2) = max{3, x2 - 5} pred!_A(x1) = 2 |0|!_A = 0 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: quot#_A(x1,x2) = max{0, x1 - 4, x2 - 7} s_A(x1) = max{4, x1 + 3} minus_A(x1,x2) = max{2, x1 + 1} pred_A(x1) = max{2, x1 - 3} |0|_A = 2 quot#!_A(x1,x2) = max{14, x1 + 13} s!_A(x1) = max{11, x1 + 9} minus!_A(x1,x2) = max{13, x1 + 10} pred!_A(x1) = max{12, x1 - 3} |0|!_A = 6 partial status: pi(quot#) = [1] pi(s) = [1] pi(minus) = [1] pi(pred) = [1] pi(|0|) = [] 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: minus#(x,s(y)) -> minus#(x,y) and R consists of: r1: pred(s(x)) -> x r2: minus(x,|0|()) -> x r3: minus(x,s(y)) -> pred(minus(x,y)) r4: quot(|0|(),s(y)) -> |0|() r5: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) 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: minus#_A(x1,x2) = 0 s_A(x1) = max{2, x1 - 2} minus#!_A(x1,x2) = max{0, x2 - 21} s!_A(x1) = max{2, x1 - 20} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: minus#_A(x1,x2) = 0 s_A(x1) = max{2, x1 - 2} minus#!_A(x1,x2) = max{3, x1 - 1, x2 - 22} s!_A(x1) = max{2, x1 - 21} partial status: pi(minus#) = [2] pi(s) = [1] The following rules are removed: p1 Then no dependency pair remains.