29 lines
792 B
VB.net
29 lines
792 B
VB.net
Function FiboBig(ByVal n As Integer) As BigInteger
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' Fibonacci sequence with BigInteger
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Dim fibn2, fibn1, fibn As BigInteger
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Dim i As Integer
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fibn = 0
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fibn2 = 0
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fibn1 = 1
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If n = 0 Then
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Return fibn2
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ElseIf n = 1 Then
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Return fibn1
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ElseIf n >= 2 Then
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For i = 2 To n
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fibn = fibn2 + fibn1
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fibn2 = fibn1
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fibn1 = fibn
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Next i
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Return fibn
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End If
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Return 0
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End Function 'FiboBig
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Sub fibotest()
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Dim i As Integer, s As String
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i = 2000000 ' 2 millions
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s = FiboBig(i).ToString
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Console.WriteLine("fibo(" & i & ")=" & s & " - length=" & Len(s))
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End Sub 'fibotest
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