Checking Puzzle Piece Positions in Excel VBA

The procedure CheckPositions() determines whether, after a swap, all puzzle pieces are arranged correctly:

Sub CheckPositions()
    Dim i As Integer
    Dim j As Integer
    Dim Name1 As String
    Dim Name2 As String
    Dim Piece1 As Shape
    Dim Piece2 As Shape
    Dim AllCorrect As Boolean
    AllCorrect = True
    ' Check horizontal order (row-wise)
    For i = 1 To 5
        For j = 1 To 4
            Name1 = "P" & i & j
            Name2 = "P" & i & (j + 1)
            Set Piece1 = ActiveSheet.Shapes(Name1)
            Set Piece2 = ActiveSheet.Shapes(Name2)
            If Piece1.Left >= Piece2.Left Then
                AllCorrect = False
                Exit For
            End If
        Next j
        If Not AllCorrect Then Exit For
    Next i
    If Not AllCorrect Then Exit Sub
    ' Check vertical order (column-wise)
    For i = 1 To 4
        For j = 1 To 5
            Name1 = "P" & i & j
            Name2 = "P" & (i + 1) & j
            Set Piece1 = ActiveSheet.Shapes(Name1)
            Set Piece2 = ActiveSheet.Shapes(Name2)
            If Piece1.Top >= Piece2.Top Then
                AllCorrect = False
                Exit For
            End If
        Next j
        If Not AllCorrect Then Exit For
    Next i
    If Not AllCorrect Then Exit Sub
    ' If all pieces are correctly positioned, end the game
    GameActive = False
    Application.OnTime Now + TimeValue("00:00:01"), _
        "PromptNewGame"
    Set Piece1 = Nothing
    Set Piece2 = Nothing
End Sub

Explanation:

• Initially, the code assumes all puzzle pieces are correctly positioned: AllCorrect = True.
• Horizontal check (row-wise):
  • For each row (i from 1 to 5), it compares horizontally adjacent pieces (j from 1 to 4).
  • It checks that piece "P" & i & j is strictly to the left of "P" & i & (j+1) using the .Left property.
  • If this condition fails, AllCorrect is set to False and the loop exits early.
• Vertical check (column-wise):
  • For each column (j from 1 to 5), it compares vertically adjacent pieces in rows (i from 1 to 4).
  • It verifies that piece "P" & i & j is above "P" & (i+1) & j using the .Top property.
  • If any piece is vertically out of order, AllCorrect is set to False, and the procedure exits.
• If any check fails, the game continues (i.e., it does not mark the puzzle as solved).
• If all pieces are correctly placed:
  • GameActive is set to False to signal the game has ended.
  • The procedure PromptNewGame() is scheduled to run one second later using Application.OnTime. This ensures visual updates finish before prompting the player.
• Finally, shape references Piece1 and Piece2 are cleared from memory.