九 种求和方法

一节课的收获

（一） Option Explicit

Private Sub Command1_Click()

Dim i As Integer

Dim a(10) As Integer

Dim sum As Integer

Randomize

For i = 1 To 10

a(i) = Int(Rnd * 1000) + 1

sum = sum + a(i)

Next i

Print sum

End Sub

（二） Private Sub Command1_Click()

Cls

Dim n As Integer, s As Integer

Dim a(10) As Integer

n = 1

While n <= 10

a(n) = Int(Rnd * 1000)

n = n + 1

Wend

n = 1

While n <= 10

Print a(n)

n = n + 1

Wend

s = 0

n = 1

While n <= 10

s = s + a(n)

n = n + 1

Wend

Print s

End Sub

（三） Dim sum As Integer

Dim i As Integer

Dim a As Integer

Private Sub Command1_Click()

sum = 0

For i = 1 To 10

Randomize

a = Int(1000 * Rnd)

sum = sum + a

MsgBox "10个随机数和为:" & sum

Next

End Sub

（四）Dim sum As Integer

Dim i As Integer

Dim a As Integer

Private Sub Command1_Click()

sum = 0

For i = 1 To 10

Randomize

a = Int(1000 * Rnd)

sum = sum + a

Next

MsgBox "10个随机数和为:" & sum

Do While i <= 10

Randomize

a = Int(1000 * Rnd)

sum = sum + a

MsgBox "10个随机数和为:" & sum

Loop

End Sub

（五） Dim sum As Integer

Dim i As Integer

Dim a As Integer

Private Sub Command1_Click()

sum = 0

For i = 1 To 10

Randomize

a = Int(1000 * Rnd)

sum = sum + a

Next

MsgBox "10个随机数和为:" & sum

i = 1

Do Until i > 10

Randomize

a = Int(1000 * Rnd)

sum = sum + a

i = i + 1

Loop

MsgBox "10个随机数和为:" & sum

End Sub

（六） Dim sum As Integer

Dim i As Integer

Dim a As Integer

Private Sub Command1_Click()

i = 1

Do

Randomize

a = Int(1000 * Rnd)

sum = sum + a

i = i + 1

Loop While i <= 10

MsgBox "10个随机数和为:" & sum

i = 1

Do

Randomize

a = Int(1000 * Rnd)

sum = sum + a

i = i + 1

Loop Until i > 10

MsgBox "10个随机数和为:" & sum

End Sub

（七）Private Sub Command1_Click()

Cls

Font.Size = 70

Print f(100)

End Sub

Private Function f(x As Integer) As Long

If x = 1 Then

f = x

Else

f = x + f(x - 1)

End If

End Function

（八） Dim sum As Integer

Dim i As Integer

Dim a As Integer

Private Sub Command1_Click()

i = 1

Do

Randomize

a = Int(1000 * Rnd)

sum = sum + a

i = i + 1

Loop While i <= 10

MsgBox "10个随机数和为:" & sum

End Sub

（九）Dim sum As Integer

Dim a As Integer

Dim i As Integer

Private Sub Command1_Click()

i = 1

Do

Randomize

a = Int(1000 * Rnd)

sum = sum + a

i = i + 1

Loop Until i > 10

MsgBox "10个随机数和为:" & sum

End Sub