YES Problem: minus(X,0()) -> X minus(s(X),s(Y)) -> p(minus(X,Y)) p(s(X)) -> X div(0(),s(Y)) -> 0() div(s(X),s(Y)) -> s(div(minus(X,Y),s(Y))) Proof: DP Processor: DPs: minus#(s(X),s(Y)) -> minus#(X,Y) minus#(s(X),s(Y)) -> p#(minus(X,Y)) div#(s(X),s(Y)) -> minus#(X,Y) div#(s(X),s(Y)) -> div#(minus(X,Y),s(Y)) TRS: minus(X,0()) -> X minus(s(X),s(Y)) -> p(minus(X,Y)) p(s(X)) -> X div(0(),s(Y)) -> 0() div(s(X),s(Y)) -> s(div(minus(X,Y),s(Y))) Usable Rule Processor: DPs: minus#(s(X),s(Y)) -> minus#(X,Y) minus#(s(X),s(Y)) -> p#(minus(X,Y)) div#(s(X),s(Y)) -> minus#(X,Y) div#(s(X),s(Y)) -> div#(minus(X,Y),s(Y)) TRS: minus(X,0()) -> X minus(s(X),s(Y)) -> p(minus(X,Y)) p(s(X)) -> X Arctic Interpretation Processor: dimension: 1 usable rules: minus(X,0()) -> X minus(s(X),s(Y)) -> p(minus(X,Y)) p(s(X)) -> X interpretation: [div#](x0, x1) = x0 + 0, [p#](x0) = 0, [minus#](x0, x1) = 1x0, [p](x0) = 1x0 + 0, [s](x0) = 2x0 + 1, [minus](x0, x1) = 1x0 + 0, [0] = 1 orientation: minus#(s(X),s(Y)) = 3X + 2 >= 1X = minus#(X,Y) minus#(s(X),s(Y)) = 3X + 2 >= 0 = p#(minus(X,Y)) div#(s(X),s(Y)) = 2X + 1 >= 1X = minus#(X,Y) div#(s(X),s(Y)) = 2X + 1 >= 1X + 0 = div#(minus(X,Y),s(Y)) minus(X,0()) = 1X + 0 >= X = X minus(s(X),s(Y)) = 3X + 2 >= 2X + 1 = p(minus(X,Y)) p(s(X)) = 3X + 2 >= X = X problem: DPs: TRS: minus(X,0()) -> X minus(s(X),s(Y)) -> p(minus(X,Y)) p(s(X)) -> X Qed