YES Problem: a__eq(0(),0()) -> true() a__eq(s(X),s(Y)) -> a__eq(X,Y) a__eq(X,Y) -> false() a__inf(X) -> cons(X,inf(s(X))) a__take(0(),X) -> nil() a__take(s(X),cons(Y,L)) -> cons(Y,take(X,L)) a__length(nil()) -> 0() a__length(cons(X,L)) -> s(length(L)) mark(eq(X1,X2)) -> a__eq(X1,X2) mark(inf(X)) -> a__inf(mark(X)) mark(take(X1,X2)) -> a__take(mark(X1),mark(X2)) mark(length(X)) -> a__length(mark(X)) mark(0()) -> 0() mark(true()) -> true() mark(s(X)) -> s(X) mark(false()) -> false() mark(cons(X1,X2)) -> cons(X1,X2) mark(nil()) -> nil() a__eq(X1,X2) -> eq(X1,X2) a__inf(X) -> inf(X) a__take(X1,X2) -> take(X1,X2) a__length(X) -> length(X) Proof: DP Processor: DPs: a__eq#(s(X),s(Y)) -> a__eq#(X,Y) mark#(eq(X1,X2)) -> a__eq#(X1,X2) mark#(inf(X)) -> mark#(X) mark#(inf(X)) -> a__inf#(mark(X)) mark#(take(X1,X2)) -> mark#(X2) mark#(take(X1,X2)) -> mark#(X1) mark#(take(X1,X2)) -> a__take#(mark(X1),mark(X2)) mark#(length(X)) -> mark#(X) mark#(length(X)) -> a__length#(mark(X)) TRS: a__eq(0(),0()) -> true() a__eq(s(X),s(Y)) -> a__eq(X,Y) a__eq(X,Y) -> false() a__inf(X) -> cons(X,inf(s(X))) a__take(0(),X) -> nil() a__take(s(X),cons(Y,L)) -> cons(Y,take(X,L)) a__length(nil()) -> 0() a__length(cons(X,L)) -> s(length(L)) mark(eq(X1,X2)) -> a__eq(X1,X2) mark(inf(X)) -> a__inf(mark(X)) mark(take(X1,X2)) -> a__take(mark(X1),mark(X2)) mark(length(X)) -> a__length(mark(X)) mark(0()) -> 0() mark(true()) -> true() mark(s(X)) -> s(X) mark(false()) -> false() mark(cons(X1,X2)) -> cons(X1,X2) mark(nil()) -> nil() a__eq(X1,X2) -> eq(X1,X2) a__inf(X) -> inf(X) a__take(X1,X2) -> take(X1,X2) a__length(X) -> length(X) Matrix Interpretation Processor: dim=1 interpretation: [mark#](x0) = x0, [a__length#](x0) = 0, [a__take#](x0, x1) = x1, [a__inf#](x0) = 0, [a__eq#](x0, x1) = x0, [mark](x0) = 4x0 + 1, [eq](x0, x1) = 2x0 + 2, [length](x0) = x0 + 1, [a__length](x0) = x0 + 2, [take](x0, x1) = x0 + 4x1 + 2, [nil] = 2, [a__take](x0, x1) = x0 + 4x1 + 2, [cons](x0, x1) = x1, [inf](x0) = 2x0 + 1, [a__inf](x0) = 2x0 + 3, [false] = 2, [s](x0) = x0 + 1, [true] = 4, [a__eq](x0, x1) = 5x0 + 2, [0] = 4 orientation: a__eq#(s(X),s(Y)) = X + 1 >= X = a__eq#(X,Y) mark#(eq(X1,X2)) = 2X1 + 2 >= X1 = a__eq#(X1,X2) mark#(inf(X)) = 2X + 1 >= X = mark#(X) mark#(inf(X)) = 2X + 1 >= 0 = a__inf#(mark(X)) mark#(take(X1,X2)) = X1 + 4X2 + 2 >= X2 = mark#(X2) mark#(take(X1,X2)) = X1 + 4X2 + 2 >= X1 = mark#(X1) mark#(take(X1,X2)) = X1 + 4X2 + 2 >= 4X2 + 1 = a__take#(mark(X1),mark(X2)) mark#(length(X)) = X + 1 >= X = mark#(X) mark#(length(X)) = X + 1 >= 0 = a__length#(mark(X)) a__eq(0(),0()) = 22 >= 4 = true() a__eq(s(X),s(Y)) = 5X + 7 >= 5X + 2 = a__eq(X,Y) a__eq(X,Y) = 5X + 2 >= 2 = false() a__inf(X) = 2X + 3 >= 2X + 3 = cons(X,inf(s(X))) a__take(0(),X) = 4X + 6 >= 2 = nil() a__take(s(X),cons(Y,L)) = 4L + X + 3 >= 4L + X + 2 = cons(Y,take(X,L)) a__length(nil()) = 4 >= 4 = 0() a__length(cons(X,L)) = L + 2 >= L + 2 = s(length(L)) mark(eq(X1,X2)) = 8X1 + 9 >= 5X1 + 2 = a__eq(X1,X2) mark(inf(X)) = 8X + 5 >= 8X + 5 = a__inf(mark(X)) mark(take(X1,X2)) = 4X1 + 16X2 + 9 >= 4X1 + 16X2 + 7 = a__take(mark(X1),mark(X2)) mark(length(X)) = 4X + 5 >= 4X + 3 = a__length(mark(X)) mark(0()) = 17 >= 4 = 0() mark(true()) = 17 >= 4 = true() mark(s(X)) = 4X + 5 >= X + 1 = s(X) mark(false()) = 9 >= 2 = false() mark(cons(X1,X2)) = 4X2 + 1 >= X2 = cons(X1,X2) mark(nil()) = 9 >= 2 = nil() a__eq(X1,X2) = 5X1 + 2 >= 2X1 + 2 = eq(X1,X2) a__inf(X) = 2X + 3 >= 2X + 1 = inf(X) a__take(X1,X2) = X1 + 4X2 + 2 >= X1 + 4X2 + 2 = take(X1,X2) a__length(X) = X + 2 >= X + 1 = length(X) problem: DPs: TRS: a__eq(0(),0()) -> true() a__eq(s(X),s(Y)) -> a__eq(X,Y) a__eq(X,Y) -> false() a__inf(X) -> cons(X,inf(s(X))) a__take(0(),X) -> nil() a__take(s(X),cons(Y,L)) -> cons(Y,take(X,L)) a__length(nil()) -> 0() a__length(cons(X,L)) -> s(length(L)) mark(eq(X1,X2)) -> a__eq(X1,X2) mark(inf(X)) -> a__inf(mark(X)) mark(take(X1,X2)) -> a__take(mark(X1),mark(X2)) mark(length(X)) -> a__length(mark(X)) mark(0()) -> 0() mark(true()) -> true() mark(s(X)) -> s(X) mark(false()) -> false() mark(cons(X1,X2)) -> cons(X1,X2) mark(nil()) -> nil() a__eq(X1,X2) -> eq(X1,X2) a__inf(X) -> inf(X) a__take(X1,X2) -> take(X1,X2) a__length(X) -> length(X) Qed