NIELIT 2017 OCT Scientific Assistant A (CS) - Section B: 10

Question

Consider an $\varepsilon$-tree CFG. If for every pair of productions $A\rightarrow u$ and $A\rightarrow v$

• A. If $\text{FIRST(u)} \cap \text{FIRST(v)}$ is empty then the CFG has to be $LL(1).$
• B. If the CFG is $LL(1)$ then $\text{FIRST(u)} \cap \text{FIRST(v)}$ has to be empty.
• C. Both $(A)$ and $(B)$
• D. None of the above

Comments

what if u and v are terminals?

Answer 1

FIRST(u) ∩ FIRST(v) is empty iff the CFG has to be LL(1).

Hence Option C should be correct.