The grammar \(S \rightarrow (S) \mid SS \mid \epsilon\) is not suitable for…

Answer: The grammar is ambiguous.

Explanation:

1. Show ambiguity with a concrete string (for example "()"):

• Derivation 1: S ⇒ (S) ⇒ (ε) ⇒ "()"

• Derivation 2: S ⇒ SS ⇒ (S)S ⇒ (ε)S ⇒ "()"

These are two distinct leftmost derivations that produce the same terminal string, so the grammar is ambiguous.

Consequence for predictive parsing:

• Predictive (LL(1)) parsers require an unambiguous grammar with no left recursion and with disjoint FIRST/FOLLOW predictions. Because this grammar is ambiguous, it cannot be directly parsed by a predictive parser.

• Note: the production S → SS also introduces left-recursive structure, which is another reason a naive top-down predictive parser would fail; both ambiguity and left recursion make this grammar unsuitable for predictive parsing without transformation.