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Given an alternative associated with a nondeterministic DFA state,
find the path of NFA states associated with the labels sequence.
Useful tracing where in the NFA, a single input sequence can be
matched. For different alts, you should get different NFA paths.
The first NFA state for all NFA paths will be the same: the starting
NFA state of the first nondeterministic alt. Imagine (A|B|A|A):
5->9-A->o
|
6->10-B->o
|
7->11-A->o
|
8->12-A->o
There are 3 nondeterministic alts. The paths should be:
5 9 ...
5 6 7 11 ...
5 6 7 8 12 ...
The NFA path matching the sample input sequence (labels) is computed
using states 9, 11, and 12 rather than 5, 7, 8 because state 5, for
example can get to all ambig paths. Must isolate for each alt (hence,
the extra state beginning each alt in my NFA structures). Here,
firstAlt=1.