% P3:
/*
p(X,Y) :- q(X,Y).               % C31

q(X,g(Y)) :- pp(X, g(f(X,Y))).  % C32

pp(X, g(F)) :- q(X, g(F)).      % C31s
*/

p1(X,Y) :- q1(X,Y).

q1(X,g(Y)) :- pp1g(X, f(X,Y)).

pp1g(X, F) :- q1g(X, F).

q1g(X, Y) :- pp1g(X, f(X,Y)).