Say whether each of the following logic programs is stratified with respect to negation.
a. |
r(X,Y) :- p(X,Y) & ~q(Y,X) r(X,Y) :- p(X,Y) & ~q(X,Y) |
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b. |
r(X,Z) :- p(X,Z) & q(X,Z) r(X,Z) :- r(X,Y) & ~r(Y,Z) |
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c. |
r(X,Z) :- p(X,Z) & ~q(X,Z) r(X,Z) :- r(X,Y) & r(Y,Z) |
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