(VAR L X X1 X2 Y )
(RULES 
        active(eq(0, 0)) -> mark(true)
        active(eq(s(X), s(Y))) -> mark(eq(X, Y))
        active(eq(X, Y)) -> mark(false)
        active(inf(X)) -> mark(cons(X, inf(s(X))))
        active(take(0, X)) -> mark(nil)
        active(take(s(X), cons(Y, L))) -> mark(cons(Y, take(X, L)))
        active(length(nil)) -> mark(0)
        active(length(cons(X, L))) -> mark(s(length(L)))
        mark(eq(X1, X2)) -> active(eq(X1, X2))
        mark(0) -> active(0)
        mark(true) -> active(true)
        mark(s(X)) -> active(s(X))
        mark(false) -> active(false)
        mark(inf(X)) -> active(inf(mark(X)))
        mark(cons(X1, X2)) -> active(cons(X1, X2))
        mark(take(X1, X2)) -> active(take(mark(X1), mark(X2)))
        mark(nil) -> active(nil)
        mark(length(X)) -> active(length(mark(X)))
        eq(mark(X1), X2) -> eq(X1, X2)
        eq(X1, mark(X2)) -> eq(X1, X2)
        eq(active(X1), X2) -> eq(X1, X2)
        eq(X1, active(X2)) -> eq(X1, X2)
        s(mark(X)) -> s(X)
        s(active(X)) -> s(X)
        inf(mark(X)) -> inf(X)
        inf(active(X)) -> inf(X)
        cons(mark(X1), X2) -> cons(X1, X2)
        cons(X1, mark(X2)) -> cons(X1, X2)
        cons(active(X1), X2) -> cons(X1, X2)
        cons(X1, active(X2)) -> cons(X1, X2)
        take(mark(X1), X2) -> take(X1, X2)
        take(X1, mark(X2)) -> take(X1, X2)
        take(active(X1), X2) -> take(X1, X2)
        take(X1, active(X2)) -> take(X1, X2)
        length(mark(X)) -> length(X)
        length(active(X)) -> length(X)
        
)