Conditional Selection with Limits on Repetition.
So it's Christmas, and your mum delegates you, for some mysterious reason, to go buy nine (9) balloons - of any of the colours red, orange, yellow, green, blue, indigo, violet, pink, milk, white,- for home decoration.
But here's the catch. You are to buy:- a minimum of 1 red balloon and a maximum of 4 red balloons;
- a minimum of 1 orange balloon and a maximum of 3 orange balloons;
- a minimum of 1 yellow balloon and a maximum of 2 yellow balloons;
- a minimum of 1 green balloon and a maximum of 4 green balloons;
- a minimum of 1 blue balloon and a maximum of 3 blue balloons;
- a minimum of 1 indigo balloon and a maximum of 2 indigo balloons;
- a minimum of 1 violet balloon and a maximum of 4 violet balloons;
- a minimum of 1 pink balloon and a maximum of 3 pink balloons;
- a minimum of 1 gray balloon and a maximum of 2 gray balloons;
- a minimum of 1 white balloon and a maximum of 4 white balloons.
With these conditions, every family member's favourite colour
is covered for, and the decoration mix is also kept lively.
This is quite a handful for you to handle...
Code for Limited Repetitive Selection in VB.Net
The code for Selection with Conditioned Repetition will be based on that for Selection with boundless Repetition.
All that is needed after Selection with limitless Repetition is a Productive, as opposed to Summative, check of the results from the Selection with unconditioned Repetition for those options that meet our conditions.
This is how our Limited Repetitive Selection algorithm in VB.Net will work.
Create a new VB.Net class file; Call it ConditionalSelection
.
Optionally, Create a new VB.Net module file; Call it Miscellaneous_ConditionalSelection
.
Type out the adjoining VB.Net algorithm for Selection with Conditioned Repetition.
VB.Net Code for ConditionalSelection Class
Inherits Selection
Private final_elements As List(Of String())
' pick only those groups that meet occurrence conditions
Public Function limitedSelection(candidates As String(), size As Integer, minimum As Integer(), maximum As Integer()) As List(Of String())
final_elements = New List(Of String())
groupSelection(candidates, size)
For i As Integer = 0 To complete_group.Count - 1
Dim state As Boolean = False
For j As Integer = 0 To words.Length - 1
' get 'word(j)' frequency/count in group
Dim count As Integer = -1
Dim k As Integer = -1
Do
k += 1
count += 1
k = Array.IndexOf(complete_group(i), words(j), k)
Loop While k > -1
' Productive boundary check
If count >= minimum(j) And count <= maximum(j) Then
state = True
Else
state = False
Exit For
End If
Next j
' skip if already in net
If state Then
final_elements.Add(complete_group(i))
End If
Next i
Return final_elements
End Function
End Class
Miscellaneous_ConditionalSelection
Sub Main()
Dim goods As String() = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"}
' minimum number of occurrences
Dim min As Integer() = {0, 0, 1, 0, 0, 1, 0, 0, 1, 0}
' maximum number of occurrences
Dim max As Integer() = {4, 3, 2, 4, 3, 2, 4, 3, 2, 4}
Dim choose As New ConditionalSelection
Dim result As List(Of String()) = choose.limitedSelection(goods, 5, min, max)
' print choices and operation
Console.Write("[ ")
For Each choice As String In choose.words
Console.Write(choice & "; ")
Next
Console.WriteLine("] conditioned selection " & choose.r & ":" & Environment.NewLine)
' print out selections nicely
Dim i As Integer = 0
For Each group As String() In result
i += 1
Console.Write(i & ": ")
For Each member As String In group
Console.Write(member & "; ")
Next
Console.WriteLine()
Next
Console.WriteLine(Environment.NewLine & "Number of ways is " & result.Count & ".")
End Sub
End Module