question on NFA and DFA generated by flex

Consider the following simple flex input:


++++++++++++++++


var v


%%


{var} {}
. {}


%%


int main()
{
    yylex();
    return 0;
}


++++++++++++++++


Running flex in trace mode (flex -T scanner.l) it tells me
about the generated NFA and DFA:


++++++++++++++++


%%
1 (v)
2 .
3 End Marker




********** beginning dump of nfa with start state 11
state # 1 257: 0, 0
state # 2 257: 0, 0
state # 3 118: 4, 0
state # 4 257: 0, 0 [1]
state # 5 257: 1, 3
state # 6 -1: 7, 0
state # 7 257: 0, 0 [2]
state # 8 257: 5, 6
state # 9 -2: 10, 0
state # 10 257: 0, 0 [3]
state # 11 257: 8, 9
********** end of dump




DFA Dump:


state # 1:
                1 4
                2 5
                3 6
state # 2:
                1 4
                2 5
                3 6
state # 3:
state # 4:
state # 5:
state # 6:
state # 3 accepts: [4]
state # 4 accepts: [2]
state # 5 accepts: [3]
state # 6 accepts: [1]


...


++++++++++++++++


Can anybody tell me what states


2 in NFA (dead state?)
3 in DFA (corresponding dead state resulting from subset construction?)
2 in DFA (alternative start state but still dead?)


are good for?


I understand that "accepts: [1]" indicates a final state accepting "v".
What is "accepts: [4]" trying to tell me? I can only see three rules...


Thanks for your help.


Uwe.

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