YES Problem: minus(x,0()) -> x minus(s(x),s(y)) -> minus(x,y) quot(0(),s(y)) -> 0() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) app(nil(),y) -> y app(add(n,x),y) -> add(n,app(x,y)) reverse(nil()) -> nil() reverse(add(n,x)) -> app(reverse(x),add(n,nil())) shuffle(nil()) -> nil() shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) concat(leaf(),y) -> y concat(cons(u,v),y) -> cons(u,concat(v,y)) less_leaves(x,leaf()) -> false() less_leaves(leaf(),cons(w,z)) -> true() less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) Proof: DP Processor: DPs: minus#(s(x),s(y)) -> minus#(x,y) quot#(s(x),s(y)) -> minus#(x,y) quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) app#(add(n,x),y) -> app#(x,y) reverse#(add(n,x)) -> reverse#(x) reverse#(add(n,x)) -> app#(reverse(x),add(n,nil())) shuffle#(add(n,x)) -> reverse#(x) shuffle#(add(n,x)) -> shuffle#(reverse(x)) concat#(cons(u,v),y) -> concat#(v,y) less_leaves#(cons(u,v),cons(w,z)) -> concat#(w,z) less_leaves#(cons(u,v),cons(w,z)) -> concat#(u,v) less_leaves#(cons(u,v),cons(w,z)) -> less_leaves#(concat(u,v),concat(w,z)) TRS: minus(x,0()) -> x minus(s(x),s(y)) -> minus(x,y) quot(0(),s(y)) -> 0() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) app(nil(),y) -> y app(add(n,x),y) -> add(n,app(x,y)) reverse(nil()) -> nil() reverse(add(n,x)) -> app(reverse(x),add(n,nil())) shuffle(nil()) -> nil() shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) concat(leaf(),y) -> y concat(cons(u,v),y) -> cons(u,concat(v,y)) less_leaves(x,leaf()) -> false() less_leaves(leaf(),cons(w,z)) -> true() less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) Usable Rule Processor: DPs: minus#(s(x),s(y)) -> minus#(x,y) quot#(s(x),s(y)) -> minus#(x,y) quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) app#(add(n,x),y) -> app#(x,y) reverse#(add(n,x)) -> reverse#(x) reverse#(add(n,x)) -> app#(reverse(x),add(n,nil())) shuffle#(add(n,x)) -> reverse#(x) shuffle#(add(n,x)) -> shuffle#(reverse(x)) concat#(cons(u,v),y) -> concat#(v,y) less_leaves#(cons(u,v),cons(w,z)) -> concat#(w,z) less_leaves#(cons(u,v),cons(w,z)) -> concat#(u,v) less_leaves#(cons(u,v),cons(w,z)) -> less_leaves#(concat(u,v),concat(w,z)) TRS: minus(x,0()) -> x minus(s(x),s(y)) -> minus(x,y) reverse(nil()) -> nil() reverse(add(n,x)) -> app(reverse(x),add(n,nil())) app(nil(),y) -> y app(add(n,x),y) -> add(n,app(x,y)) concat(leaf(),y) -> y concat(cons(u,v),y) -> cons(u,concat(v,y)) Matrix Interpretation Processor: dim=1 usable rules: minus(x,0()) -> x minus(s(x),s(y)) -> minus(x,y) reverse(nil()) -> nil() reverse(add(n,x)) -> app(reverse(x),add(n,nil())) app(nil(),y) -> y app(add(n,x),y) -> add(n,app(x,y)) concat(leaf(),y) -> y concat(cons(u,v),y) -> cons(u,concat(v,y)) interpretation: [less_leaves#](x0, x1) = 2x0 + 3/2x1 + 1/2, [concat#](x0, x1) = x0, [shuffle#](x0) = 1/2x0 + 7/2, [reverse#](x0) = 1/2x0 + 7/2, [app#](x0, x1) = 1/2x0 + 2x1, [quot#](x0, x1) = 1/2x0 + 2x1, [minus#](x0, x1) = 3/2x0 + 3, [cons](x0, x1) = 3x0 + x1 + 2, [concat](x0, x1) = x0 + x1, [leaf] = 0, [reverse](x0) = x0, [add](x0, x1) = x1 + 1, [app](x0, x1) = x0 + x1, [nil] = 0, [s](x0) = 3x0 + 2, [minus](x0, x1) = 2x0, [0] = 0 orientation: minus#(s(x),s(y)) = 9/2x + 6 >= 3/2x + 3 = minus#(x,y) quot#(s(x),s(y)) = 3/2x + 6y + 5 >= 3/2x + 3 = minus#(x,y) quot#(s(x),s(y)) = 3/2x + 6y + 5 >= x + 6y + 4 = quot#(minus(x,y),s(y)) app#(add(n,x),y) = 1/2x + 2y + 1/2 >= 1/2x + 2y = app#(x,y) reverse#(add(n,x)) = 1/2x + 4 >= 1/2x + 7/2 = reverse#(x) reverse#(add(n,x)) = 1/2x + 4 >= 1/2x + 2 = app#(reverse(x),add(n,nil())) shuffle#(add(n,x)) = 1/2x + 4 >= 1/2x + 7/2 = reverse#(x) shuffle#(add(n,x)) = 1/2x + 4 >= 1/2x + 7/2 = shuffle#(reverse(x)) concat#(cons(u,v),y) = 3u + v + 2 >= v = concat#(v,y) less_leaves#(cons(u,v),cons(w,z)) = 6u + 2v + 9/2w + 3/2z + 15/2 >= w = concat#(w,z) less_leaves#(cons(u,v),cons(w,z)) = 6u + 2v + 9/2w + 3/2z + 15/2 >= u = concat#(u,v) less_leaves#(cons(u,v),cons(w,z)) = 6u + 2v + 9/2w + 3/2z + 15/2 >= 2u + 2v + 3/2w + 3/2z + 1/2 = less_leaves#(concat(u,v),concat(w,z)) minus(x,0()) = 2x >= x = x minus(s(x),s(y)) = 6x + 4 >= 2x = minus(x,y) reverse(nil()) = 0 >= 0 = nil() reverse(add(n,x)) = x + 1 >= x + 1 = app(reverse(x),add(n,nil())) app(nil(),y) = y >= y = y app(add(n,x),y) = x + y + 1 >= x + y + 1 = add(n,app(x,y)) concat(leaf(),y) = y >= y = y concat(cons(u,v),y) = 3u + v + y + 2 >= 3u + v + y + 2 = cons(u,concat(v,y)) problem: DPs: TRS: minus(x,0()) -> x minus(s(x),s(y)) -> minus(x,y) reverse(nil()) -> nil() reverse(add(n,x)) -> app(reverse(x),add(n,nil())) app(nil(),y) -> y app(add(n,x),y) -> add(n,app(x,y)) concat(leaf(),y) -> y concat(cons(u,v),y) -> cons(u,concat(v,y)) Qed