Imports System

Imports System.Collections.Generic

Imports System.Linq

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Public Class Program

    Class CartItem

        Public Property Id As Integer

        Public Property Total As Double

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        Private Sub New()

        End Sub

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        Public Sub New(ByVal idValue As Integer)

            Id = idValue

            Total = New Random(id * 10).NextDouble() * 10

        End Sub

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        Public Overrides Function ToString() As String

            Return $"Item {Id} total: {Total}"

        End Function

    End Class

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    Public Shared Sub Main()

        Dim items As List(Of CartItem) = New List(Of CartItem)()

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        For i As Integer = 1 To 10

            Dim item = New CartItem(i)

            items.Add(item)

            Console.WriteLine($"Added {item.ToString()}")

        Next

        Console.WriteLine()

        Console.WriteLine($"Sum of all items: {GetSum(items)}")

    End Sub

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    Private Shared Function GetSum(ByVal items As List(Of CartItem)) As Double

        Return (from item as CartItem in items Select item.Total).Sum()

    End Function

End Class

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