adapting combination code for larger list
- by vbNewbie
I have the following code to generate combinations of string for a small list and would like to adapt this for a large list of over 300 string words.Can anyone suggest how to alter this code or to use a different method.
Public Class combinations
Public Shared Sub main()
Dim myAnimals As String = "cat dog horse ape hen mouse"
Dim myAnimalCombinations As String() = BuildCombinations(myAnimals)
For Each combination As String In myAnimalCombinations
'Look on the Output Tab for the results!
Console.WriteLine("(" & combination & ")")
Next combination
Console.ReadLine()
End Sub
Public Shared Function BuildCombinations(ByVal inputString As String) As String()
'Separate the sentence into useable words.
Dim wordsArray As String() = inputString.Split(" ".ToCharArray)
'A plase to store the results as we build them
Dim returnArray() As String = New String() {""}
'The 'combination level' that we're up to
Dim wordDistance As Integer = 1
'Go through all the combination levels...
For wordDistance = 1 To wordsArray.GetUpperBound(0)
'Go through all the words at this combination level...
For wordIndex As Integer = 0 To wordsArray.GetUpperBound(0) - wordDistance
'Get the first word of this combination level
Dim combination As New System.Text.StringBuilder(wordsArray(wordIndex))
'And all all the remaining words a this combination level
For combinationIndex As Integer = 1 To wordDistance
combination.Append(" " & wordsArray(wordIndex + combinationIndex))
Next combinationIndex
'Add this combination to the results
returnArray(returnArray.GetUpperBound(0)) = combination.ToString
'Add a new row to the results, ready for the next combination
ReDim Preserve returnArray(returnArray.GetUpperBound(0) + 1)
Next wordIndex
Next wordDistance
'Get rid of the last, blank row.
ReDim Preserve returnArray(returnArray.GetUpperBound(0) - 1)
'Return combinations to the calling method.
Return returnArray
End Function
End Class
