MAYBE
0.00/0.01	 The problem does not contain well-formed TRSs:
0.00/0.01	   Strict Trs:
0.00/0.01	     { U11(tt()) -> N
0.00/0.01	     , U21(tt()) -> s(plus(N, M))
0.00/0.01	     , plus(N, s(M)) -> U21(and(isNat()))
0.00/0.02	     , plus(N, 0()) -> U11(isNat())
0.00/0.02	     , and(tt()) -> X
0.00/0.02	     , isNat() -> tt()
0.00/0.02	     , isNat() -> and(isNat())
0.00/0.02	     , isNat() -> isNat() }
0.00/0.02	   StartTerms: basic terms
0.00/0.02	   Strategy: innermost
0.00/0.02	EOF