Test by Bikram | Compiler Design | Test 1 | Question: 14

Question

Consider the following grammar: 

$E' \rightarrow E$

$E \rightarrow E + Y \mid Y$

$Y \rightarrow Y ^* F \mid F$

$F \rightarrow id \mid (E)$

How many $LR(0)$ items are there in closure $(\{E' \rightarrow \cdot E\})$?

• A. $1$
• B. $6$
• C. $7$
• D. $5$

Comments

sir ..i got 6.......but i am not include  E'--->.E

Answer 1

The following are the 7 LR(0) items.
E' --> .E
E --> .E + Y

E --> .Y
Y --> .Y * F

E --> .F
F --> .id

F --> .(E)
So, Option C.

Comments

Don't we need to consider the starting production i.e.

E'' -> .E'

??

---

No, we don't. Closure of E' --> .E is asked, so we start from this production itself and include all other productions subsequently where there is a dot(.) before a non terminal at the leftmost position of rhs. And so on for the productions obtained in the process.