Pushdown automata and context-free languages
A nondeterministic pushdown automaton augments finite control with one unbounded last-in-first-out stack.
Key knowledge
A nondeterministic pushdown automaton augments finite control with one unbounded last-in-first-out stack. The languages it recognizes are exactly the context-free languages; a grammar is simulated by expanding stack variables and matching terminal symbols.
Conditions and scope
- This equivalence uses nondeterministic PDAs.
- Acceptance conventions can be translated but must be fixed consistently.
Sources · 1
References
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Evidence and review
Lecture 4 PDA definition and CFG-to-PDA construction, slides 4–11.
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Entry details
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- info-pushdown-automata
- Revision
- university-core.1
- Structured reference record
- University core expansion