* Step 1: Sum WORST_CASE(Omega(n^1),?)
    + Considered Problem:
        - Strict TRS:
            a__after(X1,X2) -> after(X1,X2)
            a__after(0(),XS) -> mark(XS)
            a__after(s(N),cons(X,XS)) -> a__after(mark(N),mark(XS))
            a__from(X) -> cons(mark(X),from(s(X)))
            a__from(X) -> from(X)
            mark(0()) -> 0()
            mark(after(X1,X2)) -> a__after(mark(X1),mark(X2))
            mark(cons(X1,X2)) -> cons(mark(X1),X2)
            mark(from(X)) -> a__from(mark(X))
            mark(s(X)) -> s(mark(X))
        - Signature:
            {a__after/2,a__from/1,mark/1} / {0/0,after/2,cons/2,from/1,s/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {a__after,a__from,mark} and constructors {0,after,cons
            ,from,s}
    + Applied Processor:
        Sum {left = someStrategy, right = someStrategy}
    + Details:
        ()
* Step 2: DecreasingLoops WORST_CASE(Omega(n^1),?)
    + Considered Problem:
        - Strict TRS:
            a__after(X1,X2) -> after(X1,X2)
            a__after(0(),XS) -> mark(XS)
            a__after(s(N),cons(X,XS)) -> a__after(mark(N),mark(XS))
            a__from(X) -> cons(mark(X),from(s(X)))
            a__from(X) -> from(X)
            mark(0()) -> 0()
            mark(after(X1,X2)) -> a__after(mark(X1),mark(X2))
            mark(cons(X1,X2)) -> cons(mark(X1),X2)
            mark(from(X)) -> a__from(mark(X))
            mark(s(X)) -> s(mark(X))
        - Signature:
            {a__after/2,a__from/1,mark/1} / {0/0,after/2,cons/2,from/1,s/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {a__after,a__from,mark} and constructors {0,after,cons
            ,from,s}
    + Applied Processor:
        DecreasingLoops {bound = AnyLoop, narrow = 10}
    + Details:
        The system has following decreasing Loops:
          mark(x){x -> after(x,y)} =
            mark(after(x,y)) ->^+ a__after(mark(x),mark(y))
              = C[mark(x) = mark(x){}]

WORST_CASE(Omega(n^1),?)