Find a sum of a combination of cells to equal a value

I have a maths problem which i am trying to solve with a macro.

I have a list of numberin column A such as

12
14
45
24
85
78
5
33

If i have a value lets say 62 which is the sum of two or more values in the
list i would like the macro to place a formula under the list of values
adding the cells which make up that total.

62 is made of 33+5+24 this would be formula i would want placed under the
list.

Any suggestions?

You can adapt this code (written by Harlan Grove). It is certainly more than
you want, but you should consider the fact that there could be multiple
solutions:


Copy the code below (written by Harlan Grove) into a code module, and set
the references as
instructed in the comments.

Then run findsums and highlight the ranges with your values when prompted.

HTH,
Bernie
MS Excel MVP

Option Explicit
'Begin VBA Code

Sub findsums()
'This *REQUIRES* VBAProject references to
'Microsoft Scripting Runtime
'Microsoft VBScript Regular Expressions 1.0 or higher

Const TOL As Double = 0.000001 'modify as needed
Dim c As Variant

Dim j As Long, k As Long, n As Long, p As Boolean
Dim s As String, t As Double, u As Double
Dim v As Variant, x As Variant, y As Variant
Dim dc1 As New Dictionary, dc2 As New Dictionary
Dim dcn As Dictionary, dco As Dictionary
Dim re As New RegExp

re.Global = True
re.IgnoreCase = True

On Error Resume Next

Set x = Application.InputBox( _
Prompt:="Enter range of values:", _
Title:="findsums", _
Default:="", _
Type:=8 _
)

If x Is Nothing Then
Err.Clear
Exit Sub
End If

y = Application.InputBox( _
Prompt:="Enter target value:", _
Title:="findsums", _
Default:="", _
Type:=1 _
)

If VarType(y) = vbBoolean Then
Exit Sub
Else
t = y
End If

On Error GoTo 0

Set dco = dc1
Set dcn = dc2

Call recsoln

For Each y In x.Value2
If VarType(y) = vbDouble Then
If Abs(t - y) < TOL Then
recsoln "+" & Format(y)

ElseIf dco.Exists(y) Then
dco(y) = dco(y) + 1

ElseIf y < t - TOL Then
dco.Add Key:=y, Item:=1

c = CDec(c + 1)
Application.StatusBar = "[1] " & Format(c)

End If

End If
Next y

n = dco.Count

ReDim v(1 To n, 1 To 3)

For k = 1 To n
v(k, 1) = dco.Keys(k - 1)
v(k, 2) = dco.Items(k - 1)
Next k

qsortd v, 1, n

For k = n To 1 Step -1
v(k, 3) = v(k, 1) * v(k, 2) + v(IIf(k = n, n, k + 1), 3)
If v(k, 3) > t Then dcn.Add Key:="+" & _
Format(v(k, 1)), Item:=v(k, 1)
Next k

On Error GoTo CleanUp
Application.EnableEvents = False
Application.Calculation = xlCalculationManual

For k = 2 To n
dco.RemoveAll
swapo dco, dcn

For Each y In dco.Keys
p = False

For j = 1 To n
If v(j, 3) < t - dco(y) - TOL Then Exit For
x = v(j, 1)
s = "+" & Format(x)
If Right(y, Len(s)) = s Then p = True
If p Then
re.Pattern = "\" & s & "(?=(\+|$))"
If re.Execute(y).Count < v(j, 2) Then
u = dco(y) + x
If Abs(t - u) < TOL Then
recsoln y & s
ElseIf u < t - TOL Then
dcn.Add Key:=y & s, Item:=u
c = CDec(c + 1)
Application.StatusBar = "[" & Format(k) & "] " & _
Format(c)
End If
End If
End If
Next j
Next y

If dcn.Count = 0 Then Exit For
Next k

If (recsoln() = 0) Then _
MsgBox Prompt:="all combinations exhausted", _
Title:="No Solution"

CleanUp:
Application.EnableEvents = True
Application.Calculation = xlCalculationAutomatic
Application.StatusBar = False

End Sub

Private Function recsoln(Optional s As String)
Const OUTPUTWSN As String = "findsums solutions" 'modify to taste

Static r As Range
Dim ws As Worksheet

If s = "" And r Is Nothing Then
On Error Resume Next
Set ws = ActiveWorkbook.Worksheets(OUTPUTWSN)
If ws Is Nothing Then
Err.Clear
Application.ScreenUpdating = False
Set ws = ActiveSheet
Set r = Worksheets.Add.Range("A1")
r.Parent.Name = OUTPUTWSN
ws.Activate
Application.ScreenUpdating = False
Else
ws.Cells.Clear
Set r = ws.Range("A1")
End If
recsoln = 0
ElseIf s = "" Then
recsoln = r.Row - 1
Set r = Nothing
Else
r.Value = s
Set r = r.Offset(1, 0)
recsoln = r.Row - 1
End If
End Function

Private Sub qsortd(v As Variant, lft As Long, rgt As Long)
'ad hoc quicksort subroutine
'translated from Aho, Weinberger & Kernighan,
'"The Awk Programming Language", page 161

Dim j As Long, pvt As Long

If (lft >= rgt) Then Exit Sub
swap2 v, lft, lft + Int((rgt - lft + 1) * Rnd)
pvt = lft
For j = lft + 1 To rgt
If v(j, 1) > v(lft, 1) Then
pvt = pvt + 1
swap2 v, pvt, j
End If
Next j

swap2 v, lft, pvt

qsortd v, lft, pvt - 1
qsortd v, pvt + 1, rgt
End Sub

Private Sub swap2(v As Variant, i As Long, j As Long)
'modified version of the swap procedure from
'translated from Aho, Weinberger & Kernighan,
'"The Awk Programming Language", page 161

Dim t As Variant, k As Long

For k = LBound(v, 2) To UBound(v, 2)
t = v(i, k)
v(i, k) = v(j, k)
v(j, k) = t
Next k
End Sub

Private Sub swapo(a As Object, b As Object)
Dim t As Object

Set t = a
Set a = b
Set b = t
End Sub
'---- end VBA code ----

--
Regards,
Tom Ogilvy


"Hervinder" wrote:

> I have a maths problem which i am trying to solve with a macro.
>
> I have a list of numberin column A such as
>
> 12
> 14
> 45
> 24
> 85
> 78
> 5
> 33
>
> If i have a value lets say 62 which is the sum of two or more values in the
> list i would like the macro to place a formula under the list of values
> adding the cells which make up that total.
>
> 62 is made of 33+5+24 this would be formula i would want placed under the
> list.
>
> Any suggestions?