We consider the following Problem:

  Strict Trs:
    {  c(c(c(y))) -> c(c(a(y, 0())))
     , c(a(a(0(), x), y)) -> a(c(c(c(0()))), y)
     , c(y) -> y}
  StartTerms: basic terms
  Strategy: innermost

Certificate: YES(?,O(n^1))

Proof:
  Arguments of following rules are not normal-forms:
  {c(c(c(y))) -> c(c(a(y, 0())))}
  
  All above mentioned rules can be savely removed.
  
  We consider the following Problem:
  
    Strict Trs:
      {  c(a(a(0(), x), y)) -> a(c(c(c(0()))), y)
       , c(y) -> y}
    StartTerms: basic terms
    Strategy: innermost
  
  Certificate: YES(?,O(n^1))
  
  Proof:
    The weightgap principle applies, where following rules are oriented strictly:
    
    TRS Component: {c(y) -> y}
    
    Interpretation of nonconstant growth:
    -------------------------------------
      The following argument positions are usable:
        Uargs(c) = {1}, Uargs(a) = {1}
      We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
      Interpretation Functions:
       c(x1) = [1 0] x1 + [1]
               [0 1]      [0]
       a(x1, x2) = [1 0] x1 + [0 0] x2 + [0]
                   [0 0]      [0 0]      [1]
       0() = [0]
             [0]
    
    The strictly oriented rules are moved into the weak component.
    
    We consider the following Problem:
    
      Strict Trs: {c(a(a(0(), x), y)) -> a(c(c(c(0()))), y)}
      Weak Trs: {c(y) -> y}
      StartTerms: basic terms
      Strategy: innermost
    
    Certificate: YES(?,O(n^1))
    
    Proof:
      The weightgap principle applies, where following rules are oriented strictly:
      
      TRS Component: {c(a(a(0(), x), y)) -> a(c(c(c(0()))), y)}
      
      Interpretation of nonconstant growth:
      -------------------------------------
        The following argument positions are usable:
          Uargs(c) = {1}, Uargs(a) = {1}
        We have the following EDA-non-satisfying and IDA(1)-non-satisfying matrix interpretation:
        Interpretation Functions:
         c(x1) = [1 0] x1 + [0]
                 [0 1]      [0]
         a(x1, x2) = [1 2] x1 + [0 0] x2 + [0]
                     [0 0]      [0 0]      [2]
         0() = [0]
               [2]
      
      The strictly oriented rules are moved into the weak component.
      
      We consider the following Problem:
      
        Weak Trs:
          {  c(a(a(0(), x), y)) -> a(c(c(c(0()))), y)
           , c(y) -> y}
        StartTerms: basic terms
        Strategy: innermost
      
      Certificate: YES(O(1),O(1))
      
      Proof:
        We consider the following Problem:
        
          Weak Trs:
            {  c(a(a(0(), x), y)) -> a(c(c(c(0()))), y)
             , c(y) -> y}
          StartTerms: basic terms
          Strategy: innermost
        
        Certificate: YES(O(1),O(1))
        
        Proof:
          Empty rules are trivially bounded

Hurray, we answered YES(?,O(n^1))