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by Boss (32.9k points) | 1k views
Is the answer B).

2 Answers

+2 votes

Answer is B).

1. True as TDP uses LMD (left most deriviation) and BUP use reverse of RMD (right most deriviation).

2. True as recursive descent parser is a kind of top-down parser built from a set of mutually recursive procedures and LR parser which is BUP uses stack .

3. Backtracking is not for bottom up parser BUP as shift-reduce parser's efficiency is from doing no backups or backtracking.

by Veteran (50.9k points)
–2 votes
B) iii
by Active (1k points)
edited by

(i) it is correct as Top down parser does left most derivartion and bottom up uses right most derivation

(ii) it is not true because LL(1) is a top down parser which uses stack and input buffer.

(iii)it's correct, Backtracking is required in both when we reach to invalid point while derivation.

I think only (ii) is wrong


I found this question in kanodia's GATE preparation book.

Answer given is B

Explanation is given as no backtracking is used in top down parsing

Ohhh i didnt read the question well i thought the question is for correct option thats why....
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