Imports System
Public Class Test
Public Shared Sub print_odd_frequencies_char(s As String)
Dim letters(256) As Integer
For i As Integer = 0 To s.Length - 1
If (Char.IsLetter(s(i))) Then
letters(Convert.ToByte(s(i))) = letters(Convert.ToByte(s(i))) + 1
End If
Next
For i As Integer = 0 To 256 - 1
If (letters(i) <> 0 And letters(i) Mod 2 <> 0) Then
Console.WriteLine("{0} {1}", Chr(i) , letters(i))
End If
Next
End Sub
Public Shared Sub Main()
Dim s As String = "vb.net programming pro oo"
print_odd_frequencies_char(s)
End Sub
End Class
' run:
'
' a 1
' b 1
' e 1
' i 1
' r 3
' t 1
' v 1