如何使用VB获得所有重复排列的总和？

Imports System

Module Module1
    Sub Main()
        Dim arr() As Integer = {1, 2, 3} ' 输入的数组
        Dim n As Integer = arr.Length ' 数组长度
        Dim sum As Integer = GetPermutationSum(arr, n) ' 调用递归函数获取总和
        Console.WriteLine("所有重复排列的总和为：" & sum)
    End Sub

    Function GetPermutationSum(ByVal arr() As Integer, ByVal n As Integer) As Integer
        ' 递归终止条件
        If n = 1 Then
            Return arr(0)
        End If

        Dim sum As Integer = 0

        ' 遍历数组元素
        For i As Integer = 0 To n - 1
            ' 交换第一个元素与当前元素
            Swap(arr, 0, i)

            ' 递归调用，获取剩余元素的重复排列总和
            sum += GetPermutationSum(arr, n - 1)

            ' 恢复数组顺序，以便下一次交换
            Swap(arr, 0, i)
        Next

        Return sum
    End Function

    Sub Swap(ByRef arr() As Integer, ByVal i As Integer, ByVal j As Integer)
        Dim temp As Integer = arr(i)
        arr(i) = arr(j)
        arr(j) = temp
    End Sub
End Module