Pushdown Automaton: CFL and the pumping lemma
Pushdown Automaton: CFL and the pumping lemma
Pushdown Automaton: CFL and the pumping lemma
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From CFG to PDA<br />
Informally:<br />
1. Place <strong>the</strong> marker symbol $ <strong>and</strong> <strong>the</strong> start variable<br />
S on <strong>the</strong> stack.<br />
2. Repeat <strong>the</strong> following steps:<br />
– If <strong>the</strong> top of <strong>the</strong> stack is a variable A:<br />
Choose a rule A→ 1 … k <strong>and</strong> substitute A with 1 … k<br />
– If <strong>the</strong> top of <strong>the</strong> stack is a terminal a:<br />
Read next input symbol <strong>and</strong> compare to a<br />
If <strong>the</strong>y don’t match, reject (die)<br />
– If top of stack is $, go to accept state<br />
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