eq(f1(A),1,[f0(A,B,C),loop_cont_f0(C)],[B=0]).
eq(f1(A),1,[f0(A,B,C)],[B=1]).
eq(f0(A,B,C),1,[f0(A-1,B,C)],[A>=0]).
eq(f0(A,B,A),0,[],[B=1]).