YES We show the termination of the TRS R: D(t()) -> |1|() D(constant()) -> |0|() D(+(x,y)) -> +(D(x),D(y)) D(*(x,y)) -> +(*(y,D(x)),*(x,D(y))) D(-(x,y)) -> -(D(x),D(y)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: D#(+(x,y)) -> D#(x) p2: D#(+(x,y)) -> D#(y) p3: D#(*(x,y)) -> D#(x) p4: D#(*(x,y)) -> D#(y) p5: D#(-(x,y)) -> D#(x) p6: D#(-(x,y)) -> D#(y) and R consists of: r1: D(t()) -> |1|() r2: D(constant()) -> |0|() r3: D(+(x,y)) -> +(D(x),D(y)) r4: D(*(x,y)) -> +(*(y,D(x)),*(x,D(y))) r5: D(-(x,y)) -> -(D(x),D(y)) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5, p6} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: D#(+(x,y)) -> D#(x) p2: D#(-(x,y)) -> D#(y) p3: D#(-(x,y)) -> D#(x) p4: D#(*(x,y)) -> D#(y) p5: D#(*(x,y)) -> D#(x) p6: D#(+(x,y)) -> D#(y) and R consists of: r1: D(t()) -> |1|() r2: D(constant()) -> |0|() r3: D(+(x,y)) -> +(D(x),D(y)) r4: D(*(x,y)) -> +(*(y,D(x)),*(x,D(y))) r5: D(-(x,y)) -> -(D(x),D(y)) The set of usable rules consists of (no rules) Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: max/plus interpretations on natural numbers: D#_A(x1) = x1 + 3 +_A(x1,x2) = max{x1 + 2, x2 + 4} -_A(x1,x2) = max{x1 + 3, x2} *_A(x1,x2) = max{x1 + 1, x2 + 1} precedence: + = - > D# > * partial status: pi(D#) = [1] pi(+) = [1, 2] pi(-) = [1, 2] pi(*) = [] 2. weighted path order base order: max/plus interpretations on natural numbers: D#_A(x1) = max{1, x1} +_A(x1,x2) = max{x1 + 1, x2} -_A(x1,x2) = max{x1, x2} *_A(x1,x2) = 0 precedence: * > + = - > D# partial status: pi(D#) = [1] pi(+) = [1, 2] pi(-) = [1, 2] pi(*) = [] The next rules are strictly ordered: p1, p2, p3, p4, p5, p6 We remove them from the problem. Then no dependency pair remains.