WORST_CASE(?,O(n^2))
* Step 1: Ara WORST_CASE(?,O(n^2))
    + Considered Problem:
        - Strict TRS:
            a__first(X1,X2) -> first(X1,X2)
            a__first(0(),X) -> nil()
            a__first(s(X),cons(Y,Z)) -> cons(mark(Y),first(X,Z))
            a__from(X) -> cons(mark(X),from(s(X)))
            a__from(X) -> from(X)
            mark(0()) -> 0()
            mark(cons(X1,X2)) -> cons(mark(X1),X2)
            mark(first(X1,X2)) -> a__first(mark(X1),mark(X2))
            mark(from(X)) -> a__from(mark(X))
            mark(nil()) -> nil()
            mark(s(X)) -> s(mark(X))
        - Signature:
            {a__first/2,a__from/1,mark/1} / {0/0,cons/2,first/2,from/1,nil/0,s/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {a__first,a__from,mark} and constructors {0,cons,first
            ,from,nil,s}
    + Applied Processor:
        Ara {heuristics_ = NoHeuristics, minDegree = 1, maxDegree = 3, araTimeout = 60, araFindStrictRules = Nothing, araSmtSolver = Z3}
    + Details:
        Signatures used:
        ----------------
          0 :: [] -(0)-> A(1, 6)
          0 :: [] -(0)-> A(7, 6)
          0 :: [] -(0)-> A(7, 12)
          a__first :: [A(1, 6) x A(7, 6)] -(2)-> A(1, 6)
          a__from :: [A(7, 6)] -(6)-> A(1, 6)
          cons :: [A(7, 6) x A(0, 0)] -(7)-> A(7, 6)
          cons :: [A(1, 6) x A(0, 0)] -(1)-> A(1, 6)
          first :: [A(7, 6) x A(13, 6)] -(7)-> A(7, 6)
          first :: [A(1, 6) x A(7, 6)] -(1)-> A(1, 6)
          first :: [A(0, 0) x A(0, 0)] -(0)-> A(0, 0)
          from :: [A(13, 6)] -(7)-> A(7, 6)
          from :: [A(0, 0)] -(0)-> A(0, 0)
          from :: [A(7, 6)] -(1)-> A(1, 6)
          mark :: [A(7, 6)] -(4)-> A(1, 6)
          nil :: [] -(0)-> A(7, 6)
          nil :: [] -(0)-> A(7, 12)
          s :: [A(1, 6)] -(1)-> A(1, 6)
          s :: [A(7, 6)] -(7)-> A(7, 6)
          s :: [A(0, 0)] -(0)-> A(0, 0)
        
        
        Cost-free Signatures used:
        --------------------------
          0 :: [] -(0)-> A_cf(0, 0)
          0 :: [] -(0)-> A_cf(6, 0)
          0 :: [] -(0)-> A_cf(10, 2)
          a__first :: [A_cf(0, 0) x A_cf(0, 0)] -(0)-> A_cf(0, 0)
          a__first :: [A_cf(6, 0) x A_cf(6, 0)] -(6)-> A_cf(6, 0)
          a__from :: [A_cf(0, 0)] -(0)-> A_cf(0, 0)
          a__from :: [A_cf(6, 0)] -(6)-> A_cf(6, 0)
          cons :: [A_cf(0, 0) x A_cf(0, 0)] -(0)-> A_cf(0, 0)
          cons :: [A_cf(6, 0) x A_cf(0, 0)] -(6)-> A_cf(6, 0)
          first :: [A_cf(0, 0) x A_cf(0, 0)] -(0)-> A_cf(0, 0)
          first :: [A_cf(6, 0) x A_cf(6, 0)] -(6)-> A_cf(6, 0)
          from :: [A_cf(0, 0)] -(0)-> A_cf(0, 0)
          from :: [A_cf(6, 0)] -(6)-> A_cf(6, 0)
          mark :: [A_cf(0, 0)] -(0)-> A_cf(0, 0)
          mark :: [A_cf(6, 0)] -(0)-> A_cf(6, 0)
          nil :: [] -(0)-> A_cf(0, 0)
          nil :: [] -(0)-> A_cf(6, 0)
          nil :: [] -(0)-> A_cf(10, 2)
          s :: [A_cf(0, 0)] -(0)-> A_cf(0, 0)
          s :: [A_cf(6, 0)] -(6)-> A_cf(6, 0)
        
        
        Base Constructor Signatures used:
        ---------------------------------
          0_A :: [] -(0)-> A(1, 0)
          0_A :: [] -(0)-> A(0, 1)
          cons_A :: [A(1, 0) x A(0, 0)] -(1)-> A(1, 0)
          cons_A :: [A(0, 1) x A(0, 0)] -(0)-> A(0, 1)
          first_A :: [A(1, 0) x A(1, 0)] -(1)-> A(1, 0)
          first_A :: [A(0, 1) x A(1, 1)] -(0)-> A(0, 1)
          from_A :: [A(1, 0)] -(1)-> A(1, 0)
          from_A :: [A(1, 1)] -(0)-> A(0, 1)
          nil_A :: [] -(0)-> A(1, 0)
          nil_A :: [] -(0)-> A(0, 1)
          s_A :: [A(1, 0)] -(1)-> A(1, 0)
          s_A :: [A(0, 1)] -(0)-> A(0, 1)
        
* Step 2: Open MAYBE
    - Strict TRS:
        a__first(X1,X2) -> first(X1,X2)
        a__first(0(),X) -> nil()
        a__first(s(X),cons(Y,Z)) -> cons(mark(Y),first(X,Z))
        a__from(X) -> cons(mark(X),from(s(X)))
        a__from(X) -> from(X)
        mark(0()) -> 0()
        mark(cons(X1,X2)) -> cons(mark(X1),X2)
        mark(first(X1,X2)) -> a__first(mark(X1),mark(X2))
        mark(from(X)) -> a__from(mark(X))
        mark(nil()) -> nil()
        mark(s(X)) -> s(mark(X))
    - Signature:
        {a__first/2,a__from/1,mark/1} / {0/0,cons/2,first/2,from/1,nil/0,s/1}
    - Obligation:
        innermost runtime complexity wrt. defined symbols {a__first,a__from,mark} and constructors {0,cons,first
        ,from,nil,s}
Following problems could not be solved:
  - Strict TRS:
      a__first(X1,X2) -> first(X1,X2)
      a__first(0(),X) -> nil()
      a__first(s(X),cons(Y,Z)) -> cons(mark(Y),first(X,Z))
      a__from(X) -> cons(mark(X),from(s(X)))
      a__from(X) -> from(X)
      mark(0()) -> 0()
      mark(cons(X1,X2)) -> cons(mark(X1),X2)
      mark(first(X1,X2)) -> a__first(mark(X1),mark(X2))
      mark(from(X)) -> a__from(mark(X))
      mark(nil()) -> nil()
      mark(s(X)) -> s(mark(X))
  - Signature:
      {a__first/2,a__from/1,mark/1} / {0/0,cons/2,first/2,from/1,nil/0,s/1}
  - Obligation:
      innermost runtime complexity wrt. defined symbols {a__first,a__from,mark} and constructors {0,cons,first
      ,from,nil,s}
WORST_CASE(?,O(n^2))