WORST_CASE(?,O(n^1))
* Step 1: NaturalPI WORST_CASE(?,O(n^1))
    + Considered Problem:
        - Strict TRS:
            f(0(),x2) -> 0()
            f(S(x),x2) -> f(x2,x)
        - Signature:
            {f/2} / {0/0,S/1}
        - Obligation:
            innermost runtime complexity wrt. defined symbols {f} and constructors {0,S}
    + Applied Processor:
        NaturalPI {shape = StronglyLinear, restrict = NoRestrict, uargs = UArgs, urules = URules, selector = Nothing}
    + Details:
        We apply a polynomial interpretation of kind constructor-based(stronglyLinear):
        The following argument positions are considered usable:
          none
        
        Following symbols are considered usable:
          {f}
        TcT has computed the following interpretation:
          p(0) = 3          
          p(S) = 1 + x1     
          p(f) = 1 + x1 + x2
        
        Following rules are strictly oriented:
         f(0(),x2) = 4 + x2    
                   > 3         
                   = 0()       
        
        f(S(x),x2) = 2 + x + x2
                   > 1 + x + x2
                   = f(x2,x)   
        
        
        Following rules are (at-least) weakly oriented:
        

WORST_CASE(?,O(n^1))