46 lines
948 B
Plaintext
46 lines
948 B
Plaintext
' FB 1.05.0 Win64
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' The biggest integer which FB supports natively is 8 bytes so unable
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' to calculate 1 millionth Hamming number without using an external
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' "bigint" library such as GMP
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Function min(x As Integer, y As Integer) As Integer
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Return IIf(x < y, x, y)
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End Function
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Function hamming(n As Integer) As Integer
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Dim h(1 To n) As Integer
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h(1) = 1
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Dim As Integer i = 1, j = 1, k = 1
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Dim As Integer x2 = 2, x3 = 3, x5 = 5
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For m As Integer = 2 To n
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h(m) = min(x2, min(x3, x5))
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If h(m) = x2 Then
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i += 1
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x2 = 2 * h(i)
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End If
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If h(m) = x3 Then
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j += 1
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x3 = 3 * h(j)
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End if
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If h(m) = x5 Then
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k += 1
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x5 = 5 * h(k)
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End If
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Next
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Return h(n)
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End Function
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Print "The first 20 Hamming numbers are :"
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For i As Integer = 1 To 20
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Print hamming(i); " ";
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Next
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Print : Print
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Print "The 1691st hamming number is :"
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Print hamming(1691)
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Print
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Print "Press any key to quit"
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Sleep
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