Public Class Form1
'Creates the arrays needed fpr the program:
'Sets the strGift array values, which are the gifts for the day
Dim strGift() As String = {"", "Partridge in a Pear Tree", "Turtle Doves", "French Hens", "Calling Birds", "Gold Rings", "Geese-a-Laying", "Swans-A-Swimming", "Maids-a-Milking", "Ladies Dancing", "Lords-a-Leaping", "Pipers Piping", "Drummers Drumming"}
Dim dblCostForDay(12) As Double
Dim dblCost(12) As Double
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
'Sets the Cost for Day 0 to be 0, because the real values needed for the array start at 1.
dblCostForDay(0) = 0
'Sets the cost of the gifts (singular quantities) for each day
dblCost(1) = 104.99
dblCost(2) = 20.0
dblCost(3) = 15.0
dblCost(4) = 99.99
dblCost(5) = 65.0
dblCost(6) = 50.0
dblCost(7) = 600.0
dblCost(8) = 5.15
dblCost(9) = 508.46
dblCost(10) = 403.91
dblCost(11) = 186.65
dblCost(12) = 185.36
End Sub
Private Sub btnDisplay_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisplay.Click
Dim i As Integer = 0
Dim j As Integer = 0
Dim k As Integer = 0
Dim dblTotalCost As Double = 0
'sets i to the input from the user for what day they want to display and howmuch it costs
i = CInt(txtInput.Text)
'Calculates the Cost for each day, which is each days cost (item price * n number of items where n is the day) + the previous days cost.
For j = 1 To 12
dblCostForDay(j) = (dblCost(j) * j) + dblCostForDay(j - 1)
Next
'Calculates the cost of all 12 days
For k = 1 To 12
dblTotalCost += dblCostForDay(k)
Next
'Outputs each gift for the day entered by the user going from the day down to day 1
lstOutput.Items.Add("The Gift[s] for Day " & i & " are: ")
For i = CInt(txtInput.Text) To 1 Step -1
lstOutput.Items.Add(i & " " & strGift(i))
Next
'Outputs the total cost of the day chosen, and the cost of all 12 days
lstOutput.Items.Add("")
lstOutput.Items.Add("The Cost for day " & txtInput.Text & " is " & FormatCurrency(dblCostForDay(CInt(txtInput.Text)), 2))
lstOutput.Items.Add("The Total Cost for all Twelve Days is " & FormatCurrency(dblTotalCost, 2))
End Sub
End Class