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Michael Sipser Edition 3 Exercise 5 Question 3 (Page No. 239)
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Find a match in the following instance of the Post Correspondence Problem.
$\begin{Bmatrix} \bigg[\dfrac{ab}{abab}\bigg],&\bigg[\dfrac{b}{a}\bigg],&\bigg[\dfrac{aba}{b}\bigg], & \bigg[\dfrac{aa}{a}\bigg] \end{Bmatrix}$
michael-sipser
theory-of-computation
turing-machine
post-correspondence-problem
proof
asked
Oct 19, 2019
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Theory of Computation
Lakshman Patel RJIT
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Michael Sipser Edition 3 Exercise 5 Question 21 (Page No. 240)
Let $AMBIG_{CFG} = \{\langle G \rangle \mid \text{G is an ambiguous CFG}\}$. Show that $AMBIG_{CFG}$ is undecidable. (Hint: Use a reduction from $PCP$ ... $a_{1},\dots,a_{k}$ are new terminal symbols. Prove that this reduction works.)
Let $AMBIG_{CFG} = \{\langle G \rangle \mid \text{G is an ambiguous CFG}\}$. Show that $AMBIG_{CFG}$ is undecidable. (Hint: Use a reduction from $PCP$ ... $a_{1},\dots,a_{k}$ are new terminal symbols. Prove that this reduction works.)
asked
Oct 19, 2019
in
Theory of Computation
Lakshman Patel RJIT
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michael-sipser
theory-of-computation
context-free-grammars
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post-correspondence-problem
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Michael Sipser Edition 3 Exercise 5 Question 19 (Page No. 240)
In the silly Post Correspondence Problem, $SPCP$, the top string in each pair has the same length as the bottom string. Show that the $SPCP$ is decidable.
In the silly Post Correspondence Problem, $SPCP$, the top string in each pair has the same length as the bottom string. Show that the $SPCP$ is decidable.
asked
Oct 19, 2019
in
Theory of Computation
Lakshman Patel RJIT
22
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michael-sipser
theory-of-computation
post-correspondence-problem
decidability
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3
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Michael Sipser Edition 3 Exercise 5 Question 18 (Page No. 240)
Show that the Post Correspondence Problem is undecidable over the binary alphabet $\Sigma = \{0,1\}$.
Show that the Post Correspondence Problem is undecidable over the binary alphabet $\Sigma = \{0,1\}$.
asked
Oct 19, 2019
in
Theory of Computation
Lakshman Patel RJIT
119
views
michael-sipser
theory-of-computation
post-correspondence-problem
decidability
proof
0
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4
32
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Michael Sipser Edition 3 Exercise 5 Question 17 (Page No. 240)
Show that the Post Correspondence Problem is decidable over the unary alphabet $\Sigma = \{1\}$.
Show that the Post Correspondence Problem is decidable over the unary alphabet $\Sigma = \{1\}$.
asked
Oct 19, 2019
in
Theory of Computation
Lakshman Patel RJIT
32
views
michael-sipser
theory-of-computation
post-correspondence-problem
decidability
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...