ceta_eq: termination proof not accepted
1: error below switch to dependency pairs
1.1: error below the reduction pair processor
 1.1.1: error when applying the reduction pair processor with usable rules to remove from the DP problem
  pairs:
  
  minus#(f(x, y)) -> minus#(y)
  minus#(f(x, y)) -> minus#(x)
  rules:
  
  minus(minus(x)) -> x
  minus(h(x)) -> h(minus(x))
  minus(f(x, y)) -> f(minus(y), minus(x))
  
   the pairs 
  minus#(f(x, y)) -> minus#(y)
  minus#(f(x, y)) -> minus#(x)
  
  could not apply the generic root reduction pair processor with the following
  SCNP-version with mu = MS and the level mapping defined by 
  pi(minus#) = [(epsilon,0),(1,0)]
  polynomial interpretration over naturals with negative constants
  Pol(minus#(x_1)) = 1
  Pol(f(x_1, x_2)) = 1 + x_2 + x_1
  problem when orienting DPs
  cannot orient pair minus#(f(x, y)) -> minus#(y) strictly:
  [(minus#(f(x, y)),0),(f(x, y),0)] >mu [(minus#(y),0),(y,0)] could not be ensured