mymath.vb

来自「是一个工资的管理系统 利用的是VB.NET和sql2000来完成的」· VB 代码 · 共 87 行

Imports System.Math
Public Class myMath
    Public isPrime As Integer = 0
    Public cPrime As Long = 0
    Dim n As Long = 3
    Dim i As Integer = 2
    Dim max As Long
    Dim min As Long
    Dim prime(100000) As Long
    Dim x As Integer = 0
    Dim y As Integer = 9
    Public Sub New(ByVal a As Long, ByVal b As Long)
        min = a
        max = b
        prime(0) = 2
        prime(1) = 3
        prime(2) = 5
        prime(3) = 7
        prime(4) = 11
        prime(5) = 13
        prime(6) = 17
        prime(7) = 19
        prime(8) = 23
    End Sub
    Private Sub chk()
        If i < Sqrt(n) Then
            While i <= Sqrt(n)
                If n Mod i = 0 Then
                    Return
                Else
                    i += 1
                End If
            End While
            If n >= min And n <= max Then
                isPrime += 1
                cPrime += n
            End If
        End If
    End Sub
    Private Sub chkNew()
        If prime(x) < Sqrt(n) Then
            While prime(x) <= Sqrt(n)
                If n Mod prime(x) = 0 Then
                    Return
                Else
                    x += 1
                End If
            End While
            If n > 23 And y < 100000 Then
                prime(y) = n
                y += 1
            End If
            If n >= min And n <= max Then
                isPrime += 1
                cPrime += n
            End If
        End If
    End Sub
    Public Sub is_prime()
        While n <= max
            chkNew()
            n += 2
            i = 2
            x = 0
        End While
    End Sub
    Public Sub is_primeNew() '~~~~~~~~~~~~~~~~~~~~~~~
        Dim newN As Long
        While newN * 6 + 1 <= max Or newN * 6 + 5 <= max
            chkNew()
            newN += 1
            i = 2
            x = 0
        End While
    End Sub
    Public Sub chknew2()

    End Sub
    Public Sub reset()
        isPrime = 0
        cPrime = 0
        n = 3
        i = 2
        x = 0
    End Sub
End Class