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Push Down Automata (PDA).

Hello,
can someone please help with solving this problem regarding push down automata. I am to write a table for the following problem.

L={number of a's in (X) is not equal to number of b's in (X)l X is {a,b,c}* }.

I could really use some help planning the it, so i can write it myself.

The components of PDA are:
q=current state
t=input symbol
s=stack top symbol
q'=next state
i=movement over input tape.
d=operation over stack.

the operations only include [. , push, pop]

acidburns
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What do you mean by 'a table'?

Rashakil Fol
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What do you mean by 'a table'?


I mean a transition table which will show that after pushing or poping an input whether the given string is accepted or rejected.

acidburns
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6 posts since Mar 2005
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Oh, so you just mean a table with two columns: input strings and acceptance/rejection?

Well, anyway, you should probably think about information storage. When you're partway through the string, what piece of information will you need to have retained about the previously read parts of the string? How are you going to represent that information? You have two places to represent that information: your current node within the graph of the automaton, and your stack. What piece of information do you need to retain and update each step of the way?

Rashakil Fol
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hey guys!!! anyone can help me how to design a PDA that ask a string and the output should be accepted. The entire input string must be read before the machine can accept the word. It is in any language!! thnk you

samerald
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could you solved this problem ,please i need it????????????/

ce.huda
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This article has been dead for over three months

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