YES Problem: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(0(),Y) -> 0() minus(s(X),Y) -> ifMinus(le(s(X),Y),s(X),Y) ifMinus(true(),s(X),Y) -> 0() ifMinus(false(),s(X),Y) -> s(minus(X,Y)) quot(0(),s(Y)) -> 0() quot(s(X),s(Y)) -> s(quot(minus(X,Y),s(Y))) Proof: DP Processor: DPs: le#(s(X),s(Y)) -> le#(X,Y) minus#(s(X),Y) -> le#(s(X),Y) minus#(s(X),Y) -> ifMinus#(le(s(X),Y),s(X),Y) ifMinus#(false(),s(X),Y) -> minus#(X,Y) quot#(s(X),s(Y)) -> minus#(X,Y) quot#(s(X),s(Y)) -> quot#(minus(X,Y),s(Y)) TRS: le(0(),Y) -> true() le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) minus(0(),Y) -> 0() minus(s(X),Y) -> ifMinus(le(s(X),Y),s(X),Y) ifMinus(true(),s(X),Y) -> 0() ifMinus(false(),s(X),Y) -> s(minus(X,Y)) quot(0(),s(Y)) -> 0() quot(s(X),s(Y)) -> s(quot(minus(X,Y),s(Y))) Usable Rule Processor: DPs: le#(s(X),s(Y)) -> le#(X,Y) minus#(s(X),Y) -> le#(s(X),Y) minus#(s(X),Y) -> ifMinus#(le(s(X),Y),s(X),Y) ifMinus#(false(),s(X),Y) -> minus#(X,Y) quot#(s(X),s(Y)) -> minus#(X,Y) quot#(s(X),s(Y)) -> quot#(minus(X,Y),s(Y)) TRS: le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) le(0(),Y) -> true() minus(0(),Y) -> 0() minus(s(X),Y) -> ifMinus(le(s(X),Y),s(X),Y) ifMinus(true(),s(X),Y) -> 0() ifMinus(false(),s(X),Y) -> s(minus(X,Y)) Matrix Interpretation Processor: dim=1 usable rules: le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) le(0(),Y) -> true() minus(0(),Y) -> 0() minus(s(X),Y) -> ifMinus(le(s(X),Y),s(X),Y) ifMinus(true(),s(X),Y) -> 0() ifMinus(false(),s(X),Y) -> s(minus(X,Y)) interpretation: [quot#](x0, x1) = 3x0 + 6x1, [ifMinus#](x0, x1, x2) = x1, [minus#](x0, x1) = x0 + 2, [le#](x0, x1) = x0, [ifMinus](x0, x1, x2) = 2x1, [minus](x0, x1) = 2x0, [false] = 0, [s](x0) = 2x0 + 3, [true] = 0, [le](x0, x1) = x1, [0] = 0 orientation: le#(s(X),s(Y)) = 2X + 3 >= X = le#(X,Y) minus#(s(X),Y) = 2X + 5 >= 2X + 3 = le#(s(X),Y) minus#(s(X),Y) = 2X + 5 >= 2X + 3 = ifMinus#(le(s(X),Y),s(X),Y) ifMinus#(false(),s(X),Y) = 2X + 3 >= X + 2 = minus#(X,Y) quot#(s(X),s(Y)) = 6X + 12Y + 27 >= X + 2 = minus#(X,Y) quot#(s(X),s(Y)) = 6X + 12Y + 27 >= 6X + 12Y + 18 = quot#(minus(X,Y),s(Y)) le(s(X),0()) = 0 >= 0 = false() le(s(X),s(Y)) = 2Y + 3 >= Y = le(X,Y) le(0(),Y) = Y >= 0 = true() minus(0(),Y) = 0 >= 0 = 0() minus(s(X),Y) = 4X + 6 >= 4X + 6 = ifMinus(le(s(X),Y),s(X),Y) ifMinus(true(),s(X),Y) = 4X + 6 >= 0 = 0() ifMinus(false(),s(X),Y) = 4X + 6 >= 4X + 3 = s(minus(X,Y)) problem: DPs: TRS: le(s(X),0()) -> false() le(s(X),s(Y)) -> le(X,Y) le(0(),Y) -> true() minus(0(),Y) -> 0() minus(s(X),Y) -> ifMinus(le(s(X),Y),s(X),Y) ifMinus(true(),s(X),Y) -> 0() ifMinus(false(),s(X),Y) -> s(minus(X,Y)) Qed