在vb.net中获得数组数组的所有可能组合

Question

我在VB.net中有几个数组。这些数组有不同的长度，我需要它们之间的组合。简单的解决方案是使用嵌套循环如在例如：

Dim Array1= {10, 11, 12} 
Dim Array2= {15} 
Dim Array3= {1,2,3} 
Dim array(2) As Object 
array(0) = Array1 
array(1) = Array2 
array(2) = Array3 

for (a = 1 to < Array1.Length - 1) 
    for (b = 1 to < Array2.Length - 1) 
     for (c = 1 to < Array3.Length - 1)    
      'Get combination 
      Next 
     Next 
Next 

Output: {10,15,1},{10,15,2},{10,15,3},{11,15,1},{11,15,2},... 

但是，真正的问题是，阵列的数量是不固定的参数（可以是3如实施例中或任何其它数目），因此嵌套循环不是解决方案。

有什么想法？

Answer 1

这里有一个快速重写了我几乎十年前写的一些代码，同时仍然使用VB.Net 2003 ...我的硬盘上有什么美好的回忆！

希望你找到它的输出有用：

10,15,1 
10,15,2 
10,15,3 
11,15,1 
11,15,2 
11,15,3 
12,15,1 
12,15,2 
12,15,3 

生成它的代码：

Public Class Form1 

    Private WithEvents FC As ArrayCombinations = Nothing 

    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click 
     If IsNothing(FC) Then 
      FC = New ArrayCombinations 
      FC.AddArray(New Integer() {10, 11, 12}) 
      FC.AddArray(New Integer() {15}) 
      FC.AddArray(New Integer() {1, 2, 3}) 
      FC.GenerateCombos() 
     End If 
    End Sub 

    Private Sub FC_combinations(combos As System.Collections.Generic.List(Of System.Collections.Generic.List(Of Integer))) Handles FC.Combinations 
     For Each combo As List(Of Integer) In combos 
      Debug.Print(String.Join(",", combo.Select(Function(i) i.ToString()))) 
     Next 
     FC = Nothing 
    End Sub 

End Class 

Public Class ArrayCombinations 

    Private Arrays As New List(Of Integer()) 
    Private WithEvents BGW As New System.ComponentModel.BackgroundWorker 
    Public Event Combinations(ByVal combos As List(Of List(Of Integer))) 

    Public Sub New() 
     BGW.WorkerReportsProgress = True 
    End Sub 

    Public Sub AddArray(ByVal values() As Integer) 
     If Not BGW.IsBusy Then 
      Arrays.Add(values) 
     End If 
    End Sub 

    Public Sub GenerateCombos() 
     If Not BGW.IsBusy Then 
      BGW.RunWorkerAsync() 
     End If 
    End Sub 

    Private Sub BGW_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BGW.DoWork 
     Dim sizes As New List(Of Integer) 
     Dim combinations As Integer 
     Dim remainder As Integer 
     Dim quotient As Integer 
     Dim combination As List(Of Integer) 
     Dim combos As New List(Of List(Of Integer)) 

     If Arrays.Count > 0 Then 
      combinations = 1 
      For Each factor() As Integer In Arrays 
       sizes.Add(factor.Count) 
       combinations = combinations * factor.Count 
      Next 

      For i As Integer = 0 To combinations - 1 
       combination = New List(Of Integer) 
       For j As Integer = 1 To Arrays.Count 
        combination.Add(Nothing) 
       Next 

       quotient = i \ sizes.Item(sizes.Count - 1) ' Integer Division 
       remainder = i Mod sizes.Item(sizes.Count - 1) 

       combination(Arrays.Count - 1) = Arrays.Item(Arrays.Count - 1)(remainder) 
       For j As Integer = (sizes.Count - 2) To 0 Step -1 
        combination.Item(j) = Arrays.Item(j)(quotient Mod sizes.Item(j)) 
        quotient = quotient \ sizes.Item(j) ' Integer Division 
       Next 
       combos.Add(combination) 
      Next 

      e.Result = combos 
     End If 
    End Sub 

    Private Sub BGW_RunWorkerCompleted(sender As Object, e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BGW.RunWorkerCompleted 
     RaiseEvent Combinations(e.Result) 
    End Sub 

End Class 

Answer 2

您可以创建一个列表来保存所有的阵列的组合值，然后按这些值回一个数组，像这样：

Dim listCombined = New List(Of Integer) 
listCombined.AddRange(array1) 
listCombined.AddRange(array2) 
listCombined.AddRange(array3) 

Dim arrayCombined As Integer() = listCombined.ToArray() 

注：此示例假设你有整型数组，但你可以将类型更改为阵列实际保存的任何类型。您还可以循环访问数组，而不是逐个为列表调用AddRange。