LR Parsers

Question

Which of the following is true with respect to LR parsers?

S1 : LR(1) requires less space for its parsing table

S2 : LALR(1) requires less space for its parsing table

S3 : SLR(1) requires more space for its parsing table

Answer given : S1 - false, S2 - true, S3 - false

We know SLR(1) and LALR(1) have equal number of states in their parsing tables. Then how will LALR(1) require less space than SLR(1) ?

Comments

 true with respect to LR parsers

LALR require less space : True

SLR require less space  : True, question said more space so it is false.

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what about SLR with respect to LALR ?

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Number of states are same hence space for  parsing table is same.

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LR(1) means CLR
in clr RR and SR both conflict resolved, rt?
So, parsing table size will be less
Answer will be
True
true
false
All are less in size than LR(0) parse

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@srestha in LR(1), we have lookahead symbols so more number of states may be created than in SLR and LALR. So S1 is false.

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yes, but we are comparing with LR(0) parser, right?

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how did you come to know? anyway even if we consider LR(0) parser, S1 is false

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See there is hell and heaven difference between LR(0) and LR(1), and u have to choose one
So, LR(1) already in option, that is why I thought it, it will be LR(0)
why S1 false?

Answer 1

Size of LR(0) and SLR(1) Table is same