•
Input:
G
= (
N
,
T
,
P
,
S
)
;
item
I
•
Output:
C
losure
(
I
)
•
Method:
•
C
losure
(
I
)
:=
{
I
};
•
Apply the following rule until
C
losure
(
I
)
cannot
be changed:
•
if
A
®
y
·
B
z
Î
C
losure
(
I
)
and
B
®
x
Î
P
then
add
B
®
·
x
to
C
losure
(
I
)
Closure of Item:
Algorithm
21/42
Note:
C
losure(
I
)
is the set of items defined by the
following algorithm: