PLAY      START
          RPUSH
                                   ; Argument field1
          ST        GR1,ARG1
          ST        GR2,ARG2
                                   ; Argument field2
          ST        GR3,ARG3
          ST        GR4,ARG4
                                   ; Init Variable
          XOR       GR0,GR0
          ST        GR0,I001
                                   ; For i = 0 To (Len(field1) - 1) Step 1
          LD        GR7,ARG1
          LD        GR7,0,GR7
          LAD       GR7,-1,GR7
          ST        GR7,T001
          XOR       GR7,GR7
          ST        GR7,I001
J001      NOP
          LD        GR1,I001
          CPA       GR1,T001
          JPL       J003
                                   ; If ((field1(i - 1) + field1(i + 1)) = ("*"c + "."c)) Then
          LD        GR7,I001
          LAD       GR7,-1,GR7
          LD        GR1,GR7
          LD        GR2,ARG1
          LD        GR2,0,GR2
          LD        GR3,ARG2
          CALL      C011
          LD        GR7,GR0
          LD        GR6,I001
          LAD       GR6,1,GR6
          LD        GR1,GR6
          LD        GR2,ARG1
          LD        GR2,0,GR2
          LD        GR3,ARG2
          CALL      C011
          LD        GR6,GR0
          ADDA      GR7,GR6
          LD        GR6,='*'
          ADDA      GR6,='.'
          SUBA      GR7,GR6
          JZE       J010
          LAD       GR7,#FFFF
J010      XOR       GR7,=#FFFF
          AND       GR7,GR7
          JZE       J005
                                   ; field2( i ) = "*"c
          LD        GR7,I001
          LD        GR1,GR7
          LD        GR2,ARG3
          LD        GR2,0,GR2
          CALL      C013
          LD        GR7,ARG4
          ADDL      GR7,GR0
          LD        GR6,='*'
          ST        GR6,0,GR7
          JUMP      J004
                                   ; Else
J005      NOP
                                   ; field2( i ) = "."c
          LD        GR7,I001
          LD        GR1,GR7
          LD        GR2,ARG3
          LD        GR2,0,GR2
          CALL      C013
          LD        GR7,ARG4
          ADDL      GR7,GR0
          LD        GR6,='.'
          ST        GR6,0,GR7
                                   ; End If
J004      NOP
                                   ; Next i
J002      NOP
          LAD       GR1,I001
          LD        GR2,0,GR1
          LAD       GR2,1,GR2
          ST        GR2,0,GR1
          JUMP      J001
J003      NOP
EXIT      NOP
          RPOP
          RET
                                   ; ByRef field1 As String [GR1,GR2]
ARG1      DS        1
ARG2      DS        1
                                   ; ByRef field2 As String [GR3,GR4]
ARG3      DS        1
ARG4      DS        1
                                   ; Dim i As Integer
I001      DS        1
T001      DS        1
                                   ; UtilLoadElement
C011      AND       GR2,GR2
          JNZ       J006
          XOR       GR0,GR0
          RET
J006      CALL      C013
          PUSH      0,GR3
          ADDL      GR3,GR0
          LD        GR0,0,GR3
          POP       GR3
          RET
                                   ; UtilSafeIndex
C013      AND       GR2,GR2
          JNZ       J007
          XOR       GR0,GR0
          RET
J007      LD        GR0,GR1
          JPL       J008
          XOR       GR0,GR0
          RET
J008      CPL       GR0,GR2
          JMI       J009
          LAD       GR0,-1
          ADDL      GR0,GR2
J009      RET
          END