sy07.frm

用VB编程实现验证歌德巴赫猜想

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "歌德巴赫猜想验证器"
   ClientHeight    =   7245
   ClientLeft      =   60
   ClientTop       =   450
   ClientWidth     =   9720
   LinkTopic       =   "Form1"
   ScaleHeight     =   7245
   ScaleWidth      =   9720
   StartUpPosition =   3  '窗口缺省
   Begin VB.PictureBox Picture1 
      BeginProperty Font 
         Name            =   "Tahoma"
         Size            =   27.75
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   735
      Left            =   3120
      ScaleHeight     =   675
      ScaleWidth      =   5475
      TabIndex        =   7
      Top             =   5760
      Width           =   5535
   End
   Begin VB.CommandButton Command1 
      Caption         =   "验 证"
      BeginProperty Font 
         Name            =   "宋体"
         Size            =   21.75
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   735
      Left            =   1320
      TabIndex        =   6
      Top             =   5760
      Width           =   1575
   End
   Begin VB.TextBox Text1 
      BeginProperty Font 
         Name            =   "Tahoma"
         Size            =   27.75
         Charset         =   0
         Weight          =   400
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   675
      Left            =   1320
      TabIndex        =   5
      Text            =   "50"
      Top             =   4680
      Width           =   5895
   End
   Begin VB.Frame Frame2 
      Caption         =   " 验证 "
      BeginProperty Font 
         Name            =   "宋体"
         Size            =   21.75
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   3855
      Left            =   600
      TabIndex        =   3
      Top             =   3000
      Width           =   8415
      Begin VB.Label Label2 
         AutoSize        =   -1  'True
         Caption         =   "请输入一个大于或等于6的偶数"
         BeginProperty Font 
            Name            =   "黑体"
            Size            =   21.75
            Charset         =   134
            Weight          =   400
            Underline       =   0   'False
            Italic          =   0   'False
            Strikethrough   =   0   'False
         EndProperty
         Height          =   435
         Left            =   720
         TabIndex        =   4
         Top             =   840
         Width           =   5880
      End
   End
   Begin VB.Frame Frame1 
      Caption         =   " 歌德巴赫猜想 "
      BeginProperty Font 
         Name            =   "宋体"
         Size            =   21.75
         Charset         =   134
         Weight          =   700
         Underline       =   0   'False
         Italic          =   0   'False
         Strikethrough   =   0   'False
      EndProperty
      Height          =   2415
      Left            =   600
      TabIndex        =   0
      Top             =   240
      Width           =   8415
      Begin VB.Label Label5 
         AutoSize        =   -1  'True
         Caption         =   "都可以分解为两个素数之和"
         BeginProperty Font 
            Name            =   "楷体_GB2312"
            Size            =   21.75
            Charset         =   134
            Weight          =   700
            Underline       =   0   'False
            Italic          =   0   'False
            Strikethrough   =   0   'False
         EndProperty
         Height          =   435
         Left            =   2160
         TabIndex        =   2
         Top             =   1560
         Width           =   5580
      End
      Begin VB.Label Label1 
         AutoSize        =   -1  'True
         Caption         =   "任何一个大于或等于6的偶数"
         BeginProperty Font 
            Name            =   "楷体_GB2312"
            Size            =   21.75
            Charset         =   134
            Weight          =   700
            Underline       =   0   'False
            Italic          =   0   'False
            Strikethrough   =   0   'False
         EndProperty
         Height          =   435
         Left            =   960
         TabIndex        =   1
         Top             =   840
         Width           =   5820
      End
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
Dim s As String * 1

Private Sub Text1_KeyPress(KeyAscii As Integer)
        s = Chr(KeyAscii)
        Select Case s
                Case "0" To "9"
                Case Else
                        KeyAscii = 0
        End Select
End Sub

Private Sub Command1_Click()
        If Val(s) Mod 2 <> 0 Or Val(Text1.Text) < 6 Then
                MsgBox "请输入大于或等于6的偶数", 0, "输入错误"
                Text1.SetFocus
                Exit Sub
        End If
        
        Picture1.Cls

        Dim i&, a&
        a = Val(Text1.Text)
        For i = 3 To a \ 2 step 2
                If sushu(i) And sushu(a - i) Then
                        Picture1.Print a & "=" & i & "+" & (a - i)
                        Exit For
                End If
        Next i
End Sub

Public Function sushu(k) As Boolean
        Dim j&
        For j = 2 To Int(Sqr(k))
                If (k Mod j) = 0 Then
                        sushu = False
                        GoTo F
                End If
        Next j
        sushu = True
F:
End Function