MAYBE

We are left with following problem, upon which TcT provides the
certificate MAYBE.

Strict Trs:
  { lcs(x, e()) -> 0()
  , lcs(e(), y) -> 0()
  , lcs(a(x), a(y)) -> s(lcs(x, y))
  , lcs(a(x), b(y)) -> max(lcs(x, b(y)), lcs(a(x), y))
  , lcs(b(x), a(y)) -> max(lcs(x, a(y)), lcs(b(x), y))
  , lcs(b(x), b(y)) -> s(lcs(x, y))
  , max(x, 0()) -> 0()
  , max(0(), y) -> 0()
  , max(s(x), s(y)) -> max(x, y) }
Obligation:
  innermost runtime complexity
Answer:
  MAYBE

The input cannot be shown compatible

Arrrr..