VB.NET判断质数

    Sub Main()
继续:
        Dim 测时 As New Diagnostics.Stopwatch
        测时.Start()
        '===============================================================================================================
        Dim 数 = 1000000000000000000
        While 数 <= 1000000000000010000
            If 判断质数(数) Then ' And 判断质数(数 + 2)
                Console.Write("{0} ", 数)
            End If
            数 += IIf(数 Mod 2 > 0, 2, 1)
        End While
        '===============================================================================================================
        测时.Stop()
        Console.WriteLine()
        Console.WriteLine("{0}毫秒，按任意键继续，按回车结束。", 测时.Elapsed.TotalMilliseconds)
        If Console.ReadKey(True).Key = ConsoleKey.Enter Then
            Return
        Else
            GoTo 继续
        End If
    End Sub

    Function 判断质数(ByVal 数 As Long) As Boolean
        Dim 除数 As Integer = 2
        Dim 开方 As Double = System.Math.Sqrt(数)
        While 开方 >= 除数
            If 数 Mod 除数 > 0 Then
                除数 = 除数 + IIf(除数 > 2, 2, 1)
            Else
                Return False
            End If
        End While
        Return True
    End Function

无标题.png (上传于2020-02-23 15:56:32)

无标题.png (上传于2020-02-23 20:30:37)