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# 逐步拾回自己
## Description
Retrieve the flag step by step.
### Attachments
excel_4891c2b27e2312569280036715a101b9.zip
## Writeup
First we entered `hkcert21{}` as we know that are the flag format, then we brute forced our way through by running the following VB script:
```vb
Function try(n)
If n Cells(1, 2) Then
found = True
For i = 4 To 29
if Cells(22, i) <> Cells (23, i) Then
found = False
End if
Next
For i = 14 To 21
If Cells(i, 30) <> Cells(i, 31) Then
found = False
End If
Next
If found = True Then
MsgBoxCells(1, 2)
End If
try = 0
Else
For ascii = 33 To 126
If ascii <> 39 Then
Cells(2, n).Value = Chr(ascii)
If Cells(22, n - 1) = Cells(23, n - 1) Then
try (n + 1)
End If
End If
Next
End If
End Function
```
and we got the flag.
## Flag
`hkcert21{funny_excel_rev}`
