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

WORST_CASE(NON_POLY,?)