求阶乘和，VB编程

Option Explicit

Private Sub Command1_Click()

Dim s As Double

Dim j As Long

Dim i As Integer

'采用过程

s = 0

For i = 1 To 10

Call Myj1(i, j)

s = s + j

Next i

Print s

Print

'采用函数

s = 0

For i = 1 To 10

s = s + Myj2(i)

Next i

Print s

End Sub

'自定义过程

Private Sub Myj1(ByVal n As Integer, ByRef j As Long)

Dim i As Integer

Dim jj As Long

jj = 1

For i = 1 To n

jj = jj * i

Next i

j = jj

End Sub

'自定义函数

Private Function Myj2(ByVal n As Integer) As Long

Dim i As Integer

Dim jj As Long

jj = 1

For i = 1 To n

jj = jj * i

Next i

Myj2 = jj

End Function

用vb求1到n的阶乘和的程序：

1.

自己编写函数代码：

Private

Function

jieC(Byval

n

As

Integer)

As

Long

Dim

i

As

Integer

Dim

Fac

As

Long

Fac

=

1

For

i

=

1

To

n

Fac

=

Fac

*

i

Next

i

jieC

=

Fac

End

Function

2.

在需要求阶乘的地方，调用该函数：

例如：

Dim

y

As

Long

y

=

jieC(10)

'求阶乘(10)将用10调用上面的自定义函数，返回10的阶乘

1）

for

i

=

1

to

n

2）

sum2

=

1

3）

for

j

=

1

to

i

4）

sum2

=

sum2

*

j

5）

next

j

6）

sum1

=

sum1

+

sum2

7）

next

i

这是循环的嵌套。内层循环（第3~5行）用来求阶乘，外层循环第6行主要来求阶乘的和，是一个累加器。

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