Imports System
Imports System.Collections.Generic
Imports System.Text
Public Class RemoveOddFrequencyCharacters_VB_NET
Public Shared Function RemoveOddFrequencyCharacters(ByVal s As String) As String
Dim frequencyMap As Dictionary(Of Char, Integer) = New Dictionary(Of Char, Integer)()
Dim chArray As Char() = s.ToCharArray()
For Each ch As Char In chArray
If frequencyMap.ContainsKey(ch) Then
frequencyMap(ch) += 1
Else
frequencyMap(ch) = 1
End If
Next
Dim result As StringBuilder = New StringBuilder()
For Each ch As Char In chArray
If frequencyMap(ch) Mod 2 = 0 Then
result.Append(ch)
End If
Next
Return result.ToString()
End Function
Public Shared Sub Main(ByVal args As String())
Dim s As String = "vb programming version 16"
s = RemoveOddFrequencyCharacters(s)
Console.WriteLine(s)
End Sub
End Class
' run:
'
' vogmmingvion
'
