Bottom-Up Parsing/LALR(1) Example 1: Difference between revisions

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Consider the following grammar.
Consider the following grammar.
<text>
<text>
A -> C x A | ε
A -> C x A | ε
B -> x C y | x C
B -> x C y | x C
C -> x B x | z
C -> x B x | z

Revision as of 18:39, 10 January 2009

Consider the following grammar. <text> A -> C x A | ε B -> x C y | x C C -> x B x | z </text>

  1. Build the LALR(1) parser table. If conflicts exist, assume YACC's behavior.
  2. Show the differences to LR(0) and SLR(1) parsers.
  3. Compact the parse table, eliminating and propagating reductions.
  4. Show the stack and input states, as well as the parser actions, for the sequence xxzxx.
  • Solution
    There is a "bug" in this solution: in the compacted table, L3 in state 10 should be in the column corresponding to y (corresponding to the shift to state 11 in the uncompacted table).
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