ceta_eq: termination proof not accepted
1: error below switch to dependency pairs
1.1: error below the dependency graph processor
 1.1.1: error when applying the reduction pair processor with usable rules to remove from the DP problem
  pairs:
  
  U11#(tt, M, N) -> U12#(tt, activate(M), activate(N))
  U12#(tt, M, N) -> plus#(activate(N), activate(M))
  plus#(N, s(M)) -> U11#(tt, M, N)
  rules:
  
  U11(tt, M, N) -> U12(tt, activate(M), activate(N))
  U12(tt, M, N) -> s(plus(activate(N), activate(M)))
  activate(X) -> X
  plus(N, 0) -> N
  plus(N, s(M)) -> U11(tt, M, N)
  
   the pairs 
  U11#(tt, M, N) -> U12#(tt, activate(M), activate(N))
  U12#(tt, M, N) -> plus#(activate(N), activate(M))
  plus#(N, s(M)) -> U11#(tt, M, N)
  
  could not apply the generic root reduction pair processor with the following
  SCNP-version with mu = MS and the level mapping defined by 
  pi(U12#) = [(epsilon,0),(2,2),(3,0)]
  pi(plus#) = [(epsilon,0),(1,0),(2,1)]
  pi(U11#) = [(epsilon,0),(2,10)]
  Argument Filter: 
  pi(U12#/3) = 1
  pi(tt/0) = []
  pi(plus#/2) = []
  pi(activate/1) = 1
  pi(s/1) = [1]
  pi(U11#/3) = 3
  
  RPO with the following precedence
  precedence(tt[0]) = 0
  precedence(plus#[2]) = 0
  precedence(s[1]) = 1
  
  precedence(_) = 0
  and the following status
  status(tt[0]) = lex
  status(plus#[2]) = lex
  status(s[1]) = lex
  
  status(_) = lex
  
  problem when orienting DPs
  cannot orient pair U11#(tt, M, N) -> U12#(tt, activate(M), activate(N)) strictly:
  [(U11#(tt, M, N),0),(M,10)] >mu [(U12#(tt, activate(M), activate(N)),0),(activate(M),2),(activate(N),0)] could not be ensured