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programmingnoob · Sep 6th, 2006, 5:16 PM

if i have posted it in a wrong section, please feel free to move it!
I have to write a context-free grammr for the language in which a sentence has 0 or more b followed by a c followed by a string of d, and the number of d equals number of b!
Problem! ... how do i keep track of the number of b?? there is no way, right? hmm
thanks!

Jimbo · Sep 6th, 2006, 7:38 PM

what if you just made sure there was a d for every b? Something like:

(Toggle Plain Text)

S = <something1>
T = <something2>b<something3>d<something4>
U = c

Just hook those up properly and you'll have it. (It's really easy if you think about it, but I didn't want to just give the answer straight out; it's a pretty easy one-liner too). If you need more explanation, I'll see if I can do a better job :o

a thing · Sep 6th, 2006, 9:57 PM

Does anyone else see the irony here?

programmingnoob · Sep 6th, 2006, 10:23 PM

Quote:

Originally Posted by Jimbo

what if you just made sure there was a d for every b? Something like:

(Toggle Plain Text)

S = <something1>
T = <something2>b<something3>d<something4>
U = c

Just hook those up properly and you'll have it. (It's really easy if you think about it, but I didn't want to just give the answer straight out; it's a pretty easy one-liner too). If you need more explanation, I'll see if I can do a better job :o

are you sure it's that easy?? btw i am not supposed to use left recursion

programmingnoob · Sep 6th, 2006, 10:24 PM

Quote:

Originally Posted by a thing

Does anyone else see the irony here?

what irony?

Dameon · Sep 6th, 2006, 10:33 PM

Quote:

Originally Posted by a thing

Does anyone else see the irony here?

Yes. Yes I do.

programmingnoob · Sep 6th, 2006, 11:03 PM

Quote:

Originally Posted by Dameon

Yes. Yes I do.

might as well share it with me? lol

a thing · Sep 7th, 2006, 6:55 PM

You want to do a project having to do with grammar in another language, yet you don't use proper grammar in English.

programmingnoob · Sep 7th, 2006, 9:21 PM

hey, so i know how to write context-free grammar for this q now, but I need practice! could you guys come up with more questions like this that requires me to write context-free grammar?
or tell me a site where i could find such questions (and their solutions!!)

Jimbo · Sep 7th, 2006, 10:25 PM

my best guess would be to google some school sites and look for homework assignments... no guarantees on getting solutions though

Sep 6th, 2006, 5:16 PM	#1
programmingnoob Hobbyist Programmer Join Date: Feb 2006 Posts: 154 Rep Power: 3	context-free grammar if i have posted it in a wrong section, please feel free to move it! I have to write a context-free grammr for the language in which a sentence has 0 or more b followed by a c followed by a string of d, and the number of d equals number of b! Problem! ... how do i keep track of the number of b?? there is no way, right? hmm thanks!

Sep 6th, 2006, 7:38 PM	#2
Jimbo Battle Programmer Join Date: Feb 2006 Location: Bellevue, WA, USA Posts: 751 Rep Power: 3	what if you just made sure there was a d for every b? Something like: (Toggle Plain Text) S = <something1> T = <something2>b<something3>d<something4> U = c S = <something1> T = <something2>b<something3>d<something4> U = c Just hook those up properly and you'll have it. (It's really easy if you think about it, but I didn't want to just give the answer straight out; it's a pretty easy one-liner too). If you need more explanation, I'll see if I can do a better job :o

Sep 6th, 2006, 9:57 PM	#3
a thing Unverified User Join Date: Aug 2005 Location: none Posts: 146 Rep Power: 0	Does anyone else see the irony here? __________________ Warning: My posts may change (dramatically) within the first 15 minutes they're posted. Got 'Nux?�GNU/Linux and other free software support. It's GNU/Linux, not just Linux.

Sep 7th, 2006, 6:55 PM	#8
a thing Unverified User Join Date: Aug 2005 Location: none Posts: 146 Rep Power: 0	You want to do a project having to do with grammar in another language, yet you don't use proper grammar in English. __________________ Warning: My posts may change (dramatically) within the first 15 minutes they're posted. Got 'Nux?�GNU/Linux and other free software support. It's GNU/Linux, not just Linux.

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Sep 7th, 2006, 9:21 PM	#9
programmingnoob Hobbyist Programmer Join Date: Feb 2006 Posts: 154 Rep Power: 3	hey, so i know how to write context-free grammar for this q now, but I need practice! could you guys come up with more questions like this that requires me to write context-free grammar? or tell me a site where i could find such questions (and their solutions!!)

Sep 7th, 2006, 10:25 PM	#10
Jimbo Battle Programmer Join Date: Feb 2006 Location: Bellevue, WA, USA Posts: 751 Rep Power: 3	my best guess would be to google some school sites and look for homework assignments... no guarantees on getting solutions though

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