1-1/2+1/3-1/4…………+1/99-1/100的多種解法

方法一：
    For i = 1 To 100
    If i Mod 2 = 0 Then
     s = s - 1 / i
     Else
     s = s + 1 / i
    End If
    Next i
    方法二：
    k = 0
    For a = 1 To 99 Step 2
     s = 1 / a - 1 / (a + 1)
     k = k + s
    Next a
    MsgBox (k)
    方法三：
    For i = 1 To 100
     s = s + (-1) ^ (i + 1) * (1 / i)
    Next i
    Text1.Text = s
    方法四：
    Private Sub Form_Load()
    s = 0
    For i = 1 To 100
    s = s + 1 / i
    Next i
    For a = 2 To 100 Step 2
    b = b + 1 / a
    Next a 請往下看
    c = s - 2 * b
    MsgBox (c)
    End Sub
    方法五：
    a = 1
    s = 0
    For i = 1 To 100
     a = (-1) ^ (i + 1) / i
     s = s + a
    Next i
    MsgBox (s)
    方法六：
    s=0
    for i=1 to 100
     s=s+(1/i)*(-1)^((i+1) mod 2)
    next i