Question

PROLOG

Exercise 7

Consider the following program.

a(X):- b(X), c(X), d(X).

a(X):- c(X), d(X).

a(X):- d(X).

b(1).

b(a).

b(2).

b(3).

d(10).

d(11).

c(3).

c(4).

Given the query ?- a(X). Write out the variable bindings that the variable X would get when the above query is run.

Exercise 4

Indicate whether the following are syntactically correct Rules.

a :- b, c, d:- e f. % Is this syntactically correct?

happy(X):- a , b. % Is this syntactically correct?

happy(X):- hasmoney(X) & has_friends(X). % Is this syntactically correct?

fun(fish):- blue(betty), bike(yamaha). % Is this syntactically correct?

Answer 1

Exercise 4

Answer

NO
YES
NO
YES

Explanation

a :- b, c, d:- e f.Is this syntactically correct?

NO

first note there is comma missing in between e and f

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happy(X):- a , b.

YES

rule is syntactically correct
but look at the X
X is not at all used with in the body of rule

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happy(X):- hasmoney(X) & has_friends(X).

NO

Please note that the & symbol will not recognized by prolog
You can use comma instead of that

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fun(fish):- blue(betty), bike(yamaha)

YES

Syntactically correct

even though there is no meaning

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all the best