<s>
such	O
as	O
different	O
kinds	O
of	O
finite	B-Architecture
automata	I-Architecture
.	O
</s>
<s>
nondeterministic	B-General_Concept
,	O
</s>
<s>
unambiguous	B-General_Concept
(	O
UFA	O
)	O
,	O
</s>
<s>
and	O
alternating	B-General_Concept
(	O
AFA	O
)	O
finite	B-Architecture
automata	I-Architecture
.	O
</s>
<s>
These	O
automata	O
can	O
also	O
be	O
two-way	B-General_Concept
(	O
2UFA	O
,	O
2SVFA	O
,	O
2AFA	O
)	O
.	O
</s>
<s>
All	O
these	O
machines	O
can	O
accept	O
exactly	O
the	O
regular	B-General_Concept
languages	I-General_Concept
.	O
</s>
<s>
For	O
any	O
two	O
types	O
of	O
finite	B-Architecture
automata	I-Architecture
,	O
</s>
<s>
NFA	O
to	O
DFA	B-General_Concept
:	O
states	O
.	O
</s>
<s>
This	O
is	O
the	O
subset	B-General_Concept
construction	I-General_Concept
by	O
Rabin	O
and	O
Scott	O
,	O
proved	O
optimal	O
by	O
Lupanov	O
.	O
</s>
<s>
UFA	O
to	O
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Leung	O
,	O
An	O
earlier	O
lower	O
bound	O
by	O
Schmidt	O
was	O
smaller	O
.	O
</s>
<s>
2DFA	O
to	O
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Kapoutsis	O
.	O
</s>
<s>
AFA	O
to	O
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Chandra	O
,	O
Kozen	O
and	O
Stockmeyer	O
.	O
</s>
<s>
2AFA	O
to	O
DFA	B-General_Concept
:	O
,	O
see	O
Ladner	O
,	O
Lipton	O
and	O
Stockmeyer	O
.	O
</s>
<s>
and	O
a	O
family	O
of	O
automata	O
X	O
(	O
DFA	B-General_Concept
,	O
NFA	O
,	O
etc	O
.	O
</s>
<s>
pioneered	O
the	O
state	B-General_Concept
complexity	I-General_Concept
of	O
operations	O
on	O
NFA	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Maslov	O
and	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Maslov	O
and	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
by	O
exchanging	O
accepting	O
and	O
rejecting	O
states	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Maslov	O
and	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Maslov	O
and	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Mirkin	O
,	O
Leiss	O
,	O
and	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
State	B-General_Concept
complexity	I-General_Concept
of	O
finite	B-Architecture
automata	I-Architecture
with	O
a	O
one-letter	O
(	O
unary	O
)	O
alphabet	O
,	O
pioneered	O
by	O
Chrobak	O
,	O
is	O
different	O
from	O
the	O
multi-letter	O
case	O
.	O
</s>
<s>
For	O
a	O
one-letter	O
alphabet	O
,	O
transformations	O
between	O
different	O
types	O
of	O
finite	B-Architecture
automata	I-Architecture
are	O
sometimes	O
more	O
efficient	O
than	O
in	O
the	O
general	O
case	O
.	O
</s>
<s>
NFA	O
to	O
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Chrobak	O
.	O
</s>
<s>
2DFA	O
to	O
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Chrobak	O
and	O
Kunc	O
and	O
Okhotin	O
.	O
</s>
<s>
2NFA	O
to	O
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Mereghetti	O
and	O
Pighizzini	O
.	O
</s>
<s>
UFA	O
to	O
DFA	B-General_Concept
:	O
,	O
see	O
Okhotin	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
<s>
DFA	B-General_Concept
:	O
states	O
,	O
see	O
Yu	O
,	O
Zhuang	O
and	O
Salomaa	O
.	O
</s>
