VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "1+1/2-1/3+1/4-....1/n"
   ClientHeight    =   3090
   ClientLeft      =   60
   ClientTop       =   450
   ClientWidth     =   4680
   LinkTopic       =   "Form1"
   ScaleHeight     =   3090
   ScaleWidth      =   4680
   StartUpPosition =   3  '窗口缺省
   Begin VB.TextBox Text2 
      BeginProperty Font 
         Name            =   "宋體"
         Size            =   21.75
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      ForeColor       =   &H00FF0000&
      Height          =   855
      Left            =   1200
      TabIndex        =   4
      Top             =   2040
      Width           =   3495
   End
   Begin VB.CommandButton Command1 
      BackColor       =   &H00FF0000&
      Caption         =   "S="
      BeginProperty Font 
         Name            =   "宋體"
         Size            =   42
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   855
      Left            =   0
      TabIndex        =   3
      Top             =   2040
      Width           =   1335
   End
   Begin VB.TextBox Text1 
      BeginProperty Font 
         Name            =   "宋體"
         Size            =   26.25
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      ForeColor       =   &H00FF0000&
      Height          =   735
      Left            =   2280
      TabIndex        =   1
      Top             =   120
      Width           =   2055
   End
   Begin VB.Label Label2 
      Caption         =   "S=1+1/2-1/3....1/n"
      BeginProperty Font 
         Name            =   "宋體"
         Size            =   21.75
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   855
      Left            =   120
      TabIndex        =   2
      Top             =   960
      Width           =   4455
   End
   Begin VB.Label Label1 
      Caption         =   "賦值N"
      BeginProperty Font 
         Name            =   "宋體"
         Size            =   26.25
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      ForeColor       =   &H00000000&
      Height          =   735
      Left            =   480
      TabIndex        =   0
      Top             =   240
      Width           =   1575
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Private Sub Command1_Click()
Dim x As Integer, y As Single
x = Text1.Text
y = 1
For i = 1 To x Step 1
    y = y + (-1) ^ i * 1 / i
Next
Text2.Text = y
End Sub