* Step 1: Sum WORST_CASE(Omega(n^1),?)
    + Considered Problem:
        - Strict TRS:
            ack(0(),y) -> s(y)
            ack(s(x),0()) -> ack(x,s(0()))
            ack(s(x),s(y)) -> ack(x,ack(s(x),y))
        - Signature:
            {ack/2} / {0/0,s/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {ack} and constructors {0,s}
    + Applied Processor:
        Sum {left = someStrategy, right = someStrategy}
    + Details:
        ()
* Step 2: DecreasingLoops WORST_CASE(Omega(n^1),?)
    + Considered Problem:
        - Strict TRS:
            ack(0(),y) -> s(y)
            ack(s(x),0()) -> ack(x,s(0()))
            ack(s(x),s(y)) -> ack(x,ack(s(x),y))
        - Signature:
            {ack/2} / {0/0,s/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {ack} and constructors {0,s}
    + Applied Processor:
        DecreasingLoops {bound = AnyLoop, narrow = 10}
    + Details:
        The system has following decreasing Loops:
          ack(s(x),y){y -> s(y)} =
            ack(s(x),s(y)) ->^+ ack(x,ack(s(x),y))
              = C[ack(s(x),y) = ack(s(x),y){}]

WORST_CASE(Omega(n^1),?)