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|
ORGANIZATION_BLOCK OB 1
BEGIN
CALL FC 1 (
N := 0,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#1
CALL FC 1 (
N := 1,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#1
CALL FC 1 (
N := 2,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#2
CALL FC 1 (
N := 3,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#6
CALL FC 1 (
N := 4,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#24
CALL FC 1 (
N := 5,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#120
CALL FC 1 (
N := 6,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#720
CALL FC 1 (
N := 7,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#5040
CALL FC 1 (
N := 8,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#40320
CALL FC 1 (
N := 9,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#362880
CALL FC 1 (
N := 10,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#3628800
CALL FC 1 (
N := 11,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#39916800
CALL FC 1 (
N := 12,
RET_VAL := MD 0,
)
__ASSERT== MD 0, L#479001600
CALL SFC 46 // STOP CPU
END_ORGANIZATION_BLOCK
FUNCTION FC 1 : DINT
TITLE = Calculate the factorial of #N
VAR_INPUT
N : INT;
END_VAR
VAR_TEMP
N_TMP : INT;
R_TMP : DINT;
END_VAR
BEGIN
// If #N is 0 or 1, #RET_VAL is 1 and recursion ends.
L #N
L 1
T #RET_VAL
<=I
BEB
// Subtract 1 from #N
-I
T #N_TMP
// Recurse: Calculate (#N - 1)!
CALL FC 1 (
N := #N_TMP,
RET_VAL := #R_TMP,
)
// Multiply: (#N - 1)! * #N
L #R_TMP
L #N
*D
T #RET_VAL
BE
END_FUNCTION
|
