ceta_eq: termination proof not accepted
1: error below switch to dependency pairs
1.1: error below the dependency graph processor
 1.1.2: error when applying the reduction pair processor with usable rules to remove from the DP problem
  pairs:
  
  f#(mark(X1), X2) -> f#(X1, X2)
  f#(X1, mark(X2)) -> f#(X1, X2)
  f#(active(X1), X2) -> f#(X1, X2)
  f#(X1, active(X2)) -> f#(X1, X2)
  rules:
  
  active(f(g(X), Y)) -> mark(f(X, f(g(X), Y)))
  f(mark(X1), X2) -> f(X1, X2)
  f(X1, mark(X2)) -> f(X1, X2)
  f(active(X1), X2) -> f(X1, X2)
  f(X1, active(X2)) -> f(X1, X2)
  g(mark(X)) -> g(X)
  g(active(X)) -> g(X)
  mark(f(X1, X2)) -> active(f(mark(X1), X2))
  mark(g(X)) -> active(g(mark(X)))
  
   the pairs 
  f#(active(X1), X2) -> f#(X1, X2)
  
  could not apply the generic root reduction pair processor with the following
  SCNP-version with mu = MS and the level mapping defined by 
  pi(f#) = [(epsilon,0),(1,1)]
  Argument Filter: 
  pi(f#/2) = []
  pi(mark/1) = 1
  pi(active/1) = [1]
  
  RPO with the following precedence
  precedence(f#[2]) = 0
  precedence(active[1]) = 1
  
  precedence(_) = 0
  and the following status
  status(f#[2]) = lex
  status(active[1]) = lex
  
  status(_) = lex
  
  problem when orienting DPs
  cannot orient pair f#(mark(X1), X2) -> f#(X1, X2) weakly:
  [(f#(mark(X1), X2),0),(mark(X1),1)] >=mu [(f#(X1, X2),0),(X1,1)] could not be ensured