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: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^1 order: standard order interpretations: quot#_A(x1,x2) = x1 + x2 s_A(x1) = x1 + 2 minus_A(x1,x2) = x1 + 1 pred_A(x1) = x1 |0|_A() = 1 2. matrix interpretations: carrier: N^1 order: standard order interpretations: quot#_A(x1,x2) = x2 s_A(x1) = 1 minus_A(x1,x2) = 2 pred_A(x1) = 0 |0|_A() = 1 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: 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 monotone reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^1 order: standard order interpretations: minus#_A(x1,x2) = x1 + x2 s_A(x1) = x1 + 1 2. matrix interpretations: carrier: N^1 order: standard order interpretations: minus#_A(x1,x2) = x1 + x2 s_A(x1) = x1 + 1 The next rules are strictly ordered: p1 r1, r2, r3, r4, r5 We remove them from the problem. Then no dependency pair remains.