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Digilogic · 02-23-2004, 08:51 PM

If I am supposed to define a finite state machine for an expression described as:

w is in (0,1)* and |w|[0] mod 3 = 1

what languages does that machine accept?

My main question is, what does the |w|[0] mean?

The []'s mean subscript...

Thanks

John Henry · 03-09-2004, 03:47 PM

Hmm. Don't know for certain about the notation in this specific context, but the |w| would mean the absolute value of w in the only context I've come across it before. That is to say take your value of w and get rid of any minus sign if there is one.

if w=x; |w|=x
if w=-x; |w|=x

easy

AngelicVampire · 03-17-2004, 06:21 PM

| also means OR

W[0] is the initial case...

So you have to accept: any number in the 0-1 range, or a number divisible by 3 but only if its the initial number...

so:

Init: Nmod3 -> Acceptor
.......0<N<1 -> Acceptor
......else -> fail and no other states
Transitions: 0<N<1 -> Acceptor
N<0|N>1 -> Fail and no other state

Something like that?

02-23-2004, 08:51 PM	#1 (permalink)
Digilogic Crazy Location: Raleigh, NC	Finite Automata question If I am supposed to define a finite state machine for an expression described as: w is in (0,1)* and \|w\|[0] mod 3 = 1 what languages does that machine accept? My main question is, what does the \|w\|[0] mean? The []'s mean subscript... Thanks __________________ "Good artists copy, great artists steal." - Pablo Picasso

03-09-2004, 03:47 PM	#2 (permalink)
John Henry Addict Location: Grey Britain	Hmm. Don't know for certain about the notation in this specific context, but the \|w\| would mean the absolute value of w in the only context I've come across it before. That is to say take your value of w and get rid of any minus sign if there is one. if w=x; \|w\|=x if w=-x; \|w\|=x easy __________________ "No one was behaving from very Buddhist motives. Then, thought Pigsy, he was hardly a Buddha, nor was he a monkey. Presently, he was a pig spirit changed into a little girl pretending to be a little boy to be offered to a water monster. It was all very simple to a pig spirit."

03-17-2004, 06:21 PM	#3 (permalink)
AngelicVampire Insane	\| also means OR W[0] is the initial case... So you have to accept: any number in the 0-1 range, or a number divisible by 3 but only if its the initial number... so: Init: Nmod3 -> Acceptor .......0<N<1 -> Acceptor ......else -> fail and no other states Transitions: 0<N<1 -> Acceptor N<0\|N>1 -> Fail and no other state Something like that?