Given the following two grammars G₁ S → AB / aaB A → a / Aa B → b G₂ S → aSbS…
2014
Given the following two grammars
G₁
S → AB / aaB
A → a / Aa
B → b
G₂
S → aSbS / bSaS / λ
- A.
G₁ is unambiguous and G₂ is unambiguous
- B.
G₁ is unambiguous and G₂ is ambiguous
- C.
G₁ is ambiguous and G₂ is unambiguous
- D.
G₁ is ambiguous and G₂ is ambiguous
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Correct answer: D
A grammar is ambiguous if a string has multiple leftmost derivations. For G₁, the string 'aab' derives via S→AB (A→aa, B→b) and directly via S→aaB.
For G₂, strings like 'ab' allow multiple parse trees using productions S→aSbS or S→bSaS. Thus, both grammars are ambiguous.
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