Results 30,501 to 30,510 of 38949
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10-10-2010, 09:34 PM #30501Originally Posted by Vivian Log in to see links
An NFA, similar to a DFA, consumes a string of input symbols. For each input symbol it transitions to a new state until all input symbols have been consumed.
Unlike a DFA, it is non-deterministic in that, for any input symbol, its next state may be any one of several possible states. Thus, in the formal definition, the next state is an element of the power set of states. This element, itself a set, represents some subset of all possible states to be considered at once.
An extension of the NFA is the NFA-lambda (also known as NFA-epsilon or the NFA with epsilon moves), which allows a transformation to a new state without consuming any input symbols. For example, if it is in state 1, with the next input symbol an a, it can move to state 2 without consuming any input symbols, and thus there is an ambiguity: is the system in state 1, or state 2, before consuming the letter a? Because of this ambiguity, it is more convenient to talk of the set of possible states the system may be in. Thus, before consuming letter a, the NFA-epsilon may be in any one of the states out of the set {1,2}. Equivalently, one may imagine that the NFA is in state 1 and 2 'at the same time': and this gives an informal hint of the powerset construction: the DFA equivalent to an NFA is defined as the one that is in the state q={1,2}. Transformations to new states without consuming an input symbol are called lambda transitions or epsilon transitions. They are usually labeled with the Greek letter λ or ε.
The notion of accepting an input is similar to that for the DFA. When the last input symbol is consumed, the NFA accepts if and only if there is some set of transitions that will take it to an accepting state. Equivalently, it rejects, if, no matter what transitions are applied, it would not end in an accepting state.
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10-10-2010, 09:57 PM #30502
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10-10-2010, 10:05 PM #30503
Downloading some of the Total War games.
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10-10-2010, 10:59 PM #30504
Watching TV and enjoying relaxing Sunday afternoon
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10-10-2010, 11:49 PM #30505
Studying, have exam tomorrow!
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11-10-2010, 12:59 AM #30506
Going to work
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11-10-2010, 03:50 AM #30507
Waking up.
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11-10-2010, 03:56 AM #30508Originally Posted by Vishay Log in to see links
Uploading
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11-10-2010, 06:01 AM #30509
Removing signatures that are the size of an entire page
Ok maybe not that big.
But too big.
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11-10-2010, 07:51 AM #30510
Just woke up...
Morning all.