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Consider the problem of determining whether a $PDA$ accepts some string of the form $\{ww \mid w \in \{0,1\}^{\ast} \}$ . Use the computation history method to show that this problem is undecidable.
in Theory of Computation 193 views

2 Answers

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Language acceptance by CFL is undecidable.

As easy as that.

Only membership, emptiness and finiteness only decidable.
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let’s assume w= 01

for ww, it will be 0101

Since the first and the last symbol is different.Hence, the problem is undecidable
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