ceta_eq: termination proof not accepted
1: error below switch to dependency pairs
1.1: error below the dependency graph processor
 1.1.3: error below the reduction pair processor
  1.1.3.1: error when applying the reduction pair processor with usable rules to remove from the DP problem
   pairs:
   
   a#(x, s(y), h) -> a#(x, y, s(h))
   a#(x, s(y), s(z)) -> a#(x, y, a(x, s(y), z))
   a#(x, s(y), s(z)) -> a#(x, s(y), z)
   rules:
   
   a(h, h, x) -> s(x)
   a(x, s(y), h) -> a(x, y, s(h))
   a(x, s(y), s(z)) -> a(x, y, a(x, s(y), z))
   a(s(x), h, z) -> a(x, z, z)
   app(nil, k) -> k
   app(l, nil) -> l
   app(cons(x, l), k) -> cons(x, app(l, k))
   sum(cons(x, nil)) -> cons(x, nil)
   sum(cons(x, cons(y, l))) -> sum(cons(a(x, y, h), l))
   
    the pairs 
   a#(x, s(y), h) -> a#(x, y, s(h))
   a#(x, s(y), s(z)) -> a#(x, y, a(x, s(y), z))
   
   could not apply the generic root reduction pair processor with the following
   SCNP-version with mu = MS and the level mapping defined by 
   pi(a#) = [(epsilon,0),(2,3)]
   Argument Filter: 
   pi(a#/3) = []
   pi(s/1) = [1]
   pi(a/3) = 3
   pi(h/0) = []
   
   RPO with the following precedence
   precedence(a#[3]) = 1
   precedence(s[1]) = 0
   precedence(h[0]) = 0
   
   precedence(_) = 0
   and the following status
   status(a#[3]) = lex
   status(s[1]) = lex
   status(h[0]) = lex
   
   status(_) = lex
   
   problem when orienting DPs
   cannot orient pair a#(x, s(y), s(z)) -> a#(x, s(y), z) weakly:
   [(a#(x, s(y), s(z)),0),(s(y),3)] >=mu [(a#(x, s(y), z),0),(s(y),3)] could not be ensured