Stationary Move
Definition:
Let
c
,
c
’ be
two
configurations
of
M.
Then,
M
makes a
stationary
move
from
c
to
c
’
according to
r
, written as
c
|
–
S
c
’
[
r
] or
,
simply,
c
|
–
S
c
’ if
c
=
x
p
a
y
,
c
’ =
x
q
b
y
and
r
:
p
a
®
q
b
S
Î
R
a
x
y
p
Illustration:
Rule:
p
a
®
q
b
S
a
x
y
p
Configuration
b
x
y
q
b
x
y
q
New Configuration
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