RosettaCodeData/Task/Pi/Visual-Basic-.NET/pi-2.visual

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Imports System, System.Numerics, System.Text
Module Program
Sub RunPiF(ByVal msg As String)
If msg.Length > 0 Then Console.WriteLine(msg)
Dim first As Boolean = True, stp As BigInteger = 360,
lim As BigInteger = stp, res As StringBuilder = New StringBuilder(),
rc As Integer = -1, u, j, k As BigInteger, q As BigInteger = 1,
r As BigInteger = 180, t As BigInteger = 60, i As BigInteger = 2,
y As Byte, et As TimeSpan, st As DateTime = DateTime.Now
While True
While i < lim
j = i << 1 : k = j + i : u = 3 * (k + 1) * (k + 2)
y = CByte(((q * (9 * k - 12) + 5 * r) / (5 * t)))
res.Append(y)
r = (q * (k + j - 2) + r - y * t) * u * 10
t *= u : q = 10 * q * (j - 1) * i : i += 1
End While
If first Then res.Insert(1, "."c) : first = False
Console.Write(res.ToString())
rc += res.Length : res.Clear() : lim += stp
If Console.KeyAvailable Then Exit While
End While
et = DateTime.Now - st : Console.ReadKey()
Console.Write(res.ToString()) : rc += res.Length
Console.WriteLine(vbLf & "Produced {0} digits in {1:n4} seconds.", rc, et.TotalSeconds)
End Sub
Sub Main(args As String())
RunPiF("Press a key to exit...")
If Diagnostics.Debugger.IsAttached Then Console.ReadKey()
End Sub
End Module