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10. Context-Free Languages & Lexers
10.1. Context-Free Grammar to PDA conversion
For each context-free grammar G:
- describe L(G)
- algoritmically construct a PDA that accepts the same language
- is the grammar ambiguous? If yes, write a non ambiguous grammar that generates the same language
- $ S \leftarrow aS | aSb | \epsilon $
- $ S \leftarrow aAA \\ A → aS | bS | a $
- $ S \leftarrow ABC \\ A \leftarrow aA | \epsilon \\ B \leftarrow bbB | b \\ C \leftarrow cC | c$
10.2. Lexer Spec
Given the following specs, construct the lexer DFA as presented in lecture 14 [1]:
- PAIRS: $ (10 | 01)* $
- ZERO_ONES: $ 01+ $
- NO_CONSEC_ONE: $ (1 | \epsilon)(01 | 0)* $
Separate the following input strings into lexemes: