(0) Obligation:

Clauses:

q(X) :- ','(p(s(s(0)), X), r(X)).
p(0, 0).
p(s(X), s(Y)) :- p(X, Y).
r(s(s(0))) :- !.
r(X) :- r(X).

Query: q(a)

(1) PrologDeterminacyProcessorProof (EQUIVALENT transformation)

The root node satisfies the determinacy criterion.

(2) YES