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•  » How can I know the number of all the possible parse trees?

## #1 2014-01-27 04:54:34

evinda
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### How can I know the number of all the possible parse trees?

Hello!!!
Let

the following grammar with
and with start symbol
:

I have to make all the possible parse trees for the word

But how can I know how many possible parse trees there are?Is there a formula with which I can find the number of all the possible parse trees?

## #2 2014-01-27 07:00:06

anonimnystefy
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### Re: How can I know the number of all the possible parse trees?

I think there are 6 of them here, since the difference between the trees will be in which order do you go through the operations (that is, those elements that correspond to P). You can go -+*,-*+,+-*,+*-,*-+ or *+-.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #3 2014-01-27 09:58:38

evinda
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### Re: How can I know the number of all the possible parse trees?

#### anonimnystefy wrote:

I think there are 6 of them here, since the difference between the trees will be in which order do you go through the operations (that is, those elements that correspond to P). You can go -+*,-*+,+-*,+*-,*-+ or *+-.

Ok..thank you very much!!!

## #4 2014-01-27 10:07:46

John E. Franklin
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### Re: How can I know the number of all the possible parse trees?

I don't know this stuff, but is the "/" being missed here?

igloo myrtilles fourmis
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