Mastermind game

Years ago, I had a coleco digits handheld game. It played the game of mastermind, where it chooses a 4 digit number and you try to guess it. You press a button and it will tell you how many digits are in the solution and if they are in the correct place.

I thought it'd be fun to try and make a mastermind game using microsoft excel.


So you choose a number, put it in A1, then set up a function like this:

=findmatchwrongpos(TEXT($A$1),TEXT(C1)

and your function would look something like this where we mark a "match" with an asterisk so it won't be counted again.

Function findmatchwrongpos(a, b As String) As Integer
  For i = 1 To Len(a)
    If Mid(a, i, 1) = Mid(b, i, 1) Then
      correctposcount = correctposcount + 1
      Mid(a, i, 1) = "*"
      Mid(b, i, 1) = "*"
    End If
  Next i
  For i = 1 To Len(a)
    c = Mid(a, i, 1)
    If c <> "*" Then
        For j = 1 To Len(b)
          If Mid(b, j, 1) = c Then
            Mid(b, j, 1) = "*"
            Mid(a, i, 1) = "*"
            wrongposcount = wrongposcount + 1
            Exit For
           End If
        Next j
    End If
  Next i
  
  findmatchwrongpos = wrongposcount
End Function

And for debugging purposes, why not have a function that returns a variant type so you can see what's going on:


=findmatchitem(TEXT($A$1),TEXT(C1),1)

passing an item number so you can get different return items:

Function findmatchitem(a, b As String, item As Integer) As Variant

  For i = 1 To Len(a)
    If Mid(a, i, 1) = Mid(b, i, 1) Then
      correctposcount = correctposcount + 1
      Mid(a, i, 1) = "*"
      Mid(b, i, 1) = "*"
    End If
  Next i
  correcta = a
  correctb = b
  For i = 1 To Len(a)
    c = Mid(a, i, 1)
    If c <> "*" Then
        For j = 1 To Len(b)
          If Mid(b, j, 1) = c Then
            Mid(b, j, 1) = "*"
            Mid(a, i, 1) = "*"
            wrongposcount = wrongposcount + 1
            Exit For
           End If
        Next j
    End If
  Next i
  
  If item = 1 Then
    findmatchitem = correctposcount
  ElseIf item = 2 Then
    findmatchitem = wrongposcount
  ElseIf item = 3 Then
    findmatchitem = "CORRECT CHECK: " + correcta + "," + correctb
  ElseIf item = 4 Then
    findmatchitem = "WRONG CHECK: " + a + "," + b
  End If
End Function

Maybe after this, I'll dig out a copy of Interplay's Learn to Program Basic and write mastermind in it.