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I have an odd PDA problem that I cant seem to construct. I haven't come across one like this before.

$L = \{w\in\{a,b\}^{*} : 3\#_{a}(w) \leq 5\#_{b}(w) \leq 4\#_{a}(w)\}$

Could I get some pointers on how to tackle such a problem like this so I can be more familiar with the approaches here.

James Combs
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1 Answers1

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It's your exercise, so you should solve it yourself... but I will give you two hints.

  1. Study the methods used in Grammar for a language with 1/3 of a's. They are helpful.

  2. Use non-determinism. Build a non-deterministic PDA. (How do you think non-determinism might help here?)

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D.W.
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