Procedure in_List(in.s)
  Define.i i, j
  Define.s a
  Restore data_to_test
  For i=1 To 3*8-1
    Read.s a
    If in=a
      ProcedureReturn #True
    EndIf
  Next i
  ProcedureReturn #False
EndProcedure

Define.c z, x, c, v
If OpenConsole()
  For z='A' To 'D'
    For x='A' To 'D'
      If z=x:Continue:EndIf
      For c='A' To 'D'
        If c=x Or c=z:Continue:EndIf
        For v='A' To 'D'
          If v=c Or v=x Or v=z:Continue:EndIf
          Define.s test=Chr(z)+Chr(x)+Chr(c)+Chr(v)
          If Not in_List(test)
            PrintN(test+" is missing.")
          EndIf
        Next
      Next
    Next
  Next
  PrintN("Press Enter to exit"):Input()
EndIf

DataSection
data_to_test:
  Data.s "ABCD","CABD","ACDB","DACB","BCDA","ACBD","ADCB","CDAB"
  Data.s "DABC","BCAD","CADB","CDBA","CBAD","ABDC","ADBC","BDCA"
  Data.s "DCBA","BACD","BADC","BDAC","CBDA","DBCA","DCAB"
EndDataSection