07.frm

一个验证歌德巴赫猜想的小程序

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Form1"
   ClientHeight    =   6165
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   5460
   LinkTopic       =   "Form1"
   ScaleHeight     =   6165
   ScaleWidth      =   5460
   StartUpPosition =   3  '窗口缺省
   Begin VB.Frame Frame2 
      Caption         =   "验证"
      Height          =   5175
      Left            =   480
      TabIndex        =   2
      Top             =   2280
      Width           =   4215
      Begin VB.PictureBox Picture1 
         Height          =   3015
         Left            =   1920
         ScaleHeight     =   2955
         ScaleWidth      =   1875
         TabIndex        =   6
         Top             =   1680
         Width           =   1935
      End
      Begin VB.CommandButton Command1 
         Caption         =   "验证"
         Height          =   375
         Left            =   480
         TabIndex        =   5
         Top             =   1800
         Width           =   855
      End
      Begin VB.TextBox Text1 
         Height          =   375
         Left            =   480
         TabIndex        =   4
         Top             =   1080
         Width           =   3015
      End
      Begin VB.Label Label2 
         Caption         =   "请输入一个大于或等于6的偶数"
         BeginProperty Font 
            Name            =   "华文行楷"
            Size            =   12
            Charset         =   134
            Weight          =   400
            Underline       =   0   'False
            Italic          =   0   'False
            Strikethrough   =   0   'False
         EndProperty
         Height          =   375
         Left            =   360
         TabIndex        =   3
         Top             =   480
         Width           =   3375
      End
   End
   Begin VB.Frame Frame1 
      Caption         =   "歌德巴赫猜想"
      Height          =   1095
      Left            =   480
      TabIndex        =   0
      Top             =   240
      Width           =   4215
      Begin VB.Label Label1 
         Caption         =   "任何大于或等于6的偶数                     都可以分解为两个素数之和"
         BeginProperty Font 
            Name            =   "华文行楷"
            Size            =   10.5
            Charset         =   134
            Weight          =   400
            Underline       =   0   'False
            Italic          =   0   'False
            Strikethrough   =   0   'False
         EndProperty
         Height          =   495
         Left            =   720
         TabIndex        =   1
         Top             =   360
         Width           =   2895
      End
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False

Public Function sushu(n As Long) As Integer
Dim i As Long
For j = 2 To n
 For i = 2 To Int(Sqr(j))
   If (j Mod i) = 0 Then
   sushu = -1
   GoTo no
  End If
 Next i
sushu = 1
no:
Next j
End Function

Private Sub Command1_Click()
Dim n As Long, m As Long
Picture1.Cls
n = Text1.Text
If Text1.Text < 6 And Text1.Text Mod 2 <> 0 Then
    MsgBox "输入信息错误，请重新输入"
ElseIf n >= 6 And (n Mod 2) = 0 Then
    For m = 3 To n \ 2
        If sushu(m) = 1 And sushu(n - m) = 1 Then
            Picture1.Print n & "=" & m & "+" & (n - m)
        End If
    Next m
End If
End Sub