code:
;****************************************************************************
;
;SCRIPT/FUNCTION : MOAN()
;
;ACTION          : Depending on the input, returns IP-addresses, Subnets, 
;                   NetworkIDs or Yes-/No-is_in_subnet
;
;AUTHOR          : Jooel Nieminen and Howard Bullock
;
;CONTRIBUTORS    : Patrick Rutten (MightyR1@hotmail.com)
;                  - making the code readable
;
;VERSION         : 1.0
;                  - 2003-06-05 Initial Release
;
;SYNTAX          : MOAN($IP, $NetworkID, $SubnetMask)
;
;PARAMETERS      : 
;
;RETURNS         : Input:  IP, NetworkID, SubnetMask
;                  Output: 1 If the IP is a member of a network defined 
;                          by NetworkID AND SubnetMask, otherwise 0
;
;                  Input:  IP, NetworkID
;                  Output: Array of all potential SubnetMasks 
;                          (CIDR notation) OR empty string If no match
;
;                  Input:  IP, SubnetMask
;                  Output: NetworkID OR empty string If no match
;
;                  Input:  NetworkID, SubnetMask
;                  Output: Array of all potential IP addresses OR 
;                          empty string If no match
;
;REMARKS         : This UDF is a result of a KiXGolf Tournament hosted by
;                   Sealeopard. Follow the links below to see how the game
;                   was played.
;
;                  Assumption: Network/broadcast addresses are NOT
;                   available as regular IP addresses though RFC3021 
;                   allows /31 networks (two IP addresses where the 
;                   network/broadcast addresses are used as regular 
;                   IP addresses)
;
;                  At least two input parameters must be provided.
;
;                  If the output consists of an array of IP addresses,
;                   then the IP addresses must be sorted In ascending order.
;
;                  The subnet mask $SubnetMask can be either the traditional 
;                   four-octets OR the alternate CIDR number, 
;                   e.g. 255.255.255.0 AND 24.
;
;                  The parameters can contain up to two spaces between the 
;                   decimal points AND the number, e.g. 192.168.0.10 AND
;                   192.168.  0. 10 should be treated the same.
;
;DEPENDENCIES    : 
;
;EXAMPLE(S)      : 
;                 [Example 1]
;                 IP=192.168.1.2
;                 NetworkID=192.168.1.0
;                 SubnetMask=255.255.255.0
;                 MOAN=1
;
;                 [Example 2]
;                 IP=192.168.0.1
;                 NetworkID=192.168.1.0
;                 SubnetMask=255.255.255.0
;                 MOAN=0
;
;                 [Example 3]
;                 IP=
;                 NetworkID=10.10.5.4
;                 SubnetMask=255.255.255.252
;                 MOAN=10.10.5.5,10.10.5.6
;
;                 [Example 4]
;                 IP=192.10.128.55
;                 NetworkID=
;                 SubnetMask=27
;                 MOAN=192.10.128.32
;
;                 [Example 5]
;                 IP=10.10.10.2
;                 NetworkID=
;                 SubnetMask=255.255.255.254
;                 MOAN=
;
;                 [Example 6]
;                 IP=10.10.10.2
;                 NetworkID=10.10.10.0
;                 SubnetMask=
;                 MOAN=/23,/24,/25,/26,/27,/28,/29,/30
;
;                 [Example 7]
;                 IP=192.168.99.55
;                 NetworkID=192.168.99.55
;                 SubnetMask=
;                 MOAN=
;
;KNOWN ISSUES    : 
;
;KIXTART VER     : 4.2x
; 
;KIXTART BBS     : KiXGolf: MOAN(), Mother Of All Networks -->
;                  - http://www.kixtart.org/board/ultimatebb.php?ubb=get_topic;f=14;t=000720
;
;                  KixGolf: MOAN(), Part II -->
;                  - http://www.kixtart.org/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=14;t=000748
;
;****************************************************************************
;
;!
Function MOAN($IP,$NetworkID,$SubnetMask)
 
 ;declaring variables
 Dim $cidrarray,$dot,$dummy,$subnetarray,$count,$help,$maskarray[3],$count2
 Dim $first,$second,$third,$fourth
 
 $cidrarray=0,128,192,224,240,248,252,254
 $dot="."

 ;build SubnetMask; starting from bit 8 through 31
 For $count=8 to 31
 
  $dummy=$count
  $help=1
 
  ;determine each octet
  For $count2=0 to 3
 
 
   ;if bitnumber/8 > 0, the octet is 255 else the mod must be determined
   ;255.255.248.0=11111111.11111111.11111000.00000000
   $maskarray[$count2]=IIf($dummy/8,255,$cidrarray[$dummy mod 8])
 
   ;8 must be substracted if one "moves" to the next octed
   $dummy=($dummy>8)*($dummy-8)
 
   ;& the IP, NetworkID and the SubnetMask octets to see if the are "compatible"
   If $IP & $NetworkID
    $help=$help & Split($NetworkID,$dot)[$count2]=(0+Split($IP,$dot)[$count2] & $maskarray[$count2])
   EndIf
  Next
 
  ;if all variables are "compatible", add the bit number to the subnet string in CIDR notation 
  If $help
   $subnetMask=$SubnetMask+" /"+$count
  EndIf
 
  ;if current bit=current subnetmask then convert the SubnetMask to
  ;normal notation, e.g. 255.255.248.0 
  If $count=$SubnetMask
   $SubnetMask=Join($maskarray,$dot)
  EndIf
 
 Next
 ;end Built subnet mask
 
 $MOAN=$SubnetMask
 
 ;if the SubnetMask contains a point, calculate IP-addresses, NetworkIDs
 ;or Yes-/No-is_in_subnet
 If InStr($SubnetMask,$dot)
 
  $dummy=Split($SubnetMask+$dot+$NetworkID,$dot)
  $MOAN=""
 
  ;if IP is provided, determine NetworkIDs
  If $IP
 
   ;calculate the NetworkID
   For $count=0 to 3
    $MOAN=$MOAN+$dot+(0+$dummy[$count] & 0+Split($IP,$dot)[$count])
   Next
 
   ;if IP=NetworkID there is no subnet, thus returning empty
   If $dot+Join(Split($IP),"")=$MOAN
    $MOAN=""
   EndIf
 
   ;if NetworkID is provided:
   ; - return .0 if the calculated NetworkID <> provided NetworkID,
   ;    IP is not in subnet
   ; - return .1 if the calculated NetworkID = provided NetworkID
   ;    IP is in subnet
   If $NetworkID
    $MOAN=$dot+Join(Split($NetworkID),"")=$MOAN
   EndIf
 
  ;determine array of IP numbers
  Else
 
   ;first octet
   For $first=$dummy[4] to 255 + $dummy[4]  - $dummy[0]
 
    ;second octet
    For $second=$dummy[5] to 255 + $dummy[5] - $dummy[1]
 
     ;Third octet
     For $third=$dummy[6] to 255 + $dummy[6] - $dummy[2]
 
      ;Fourth octet
      For $fourth=1+$dummy[7] to 254 + $dummy[7] - $dummy[3]
 
       $MOAN = $MOAN+" "+$first+$dot+$second+$dot+$third+$dot+$fourth
      Next
 
     Next
 
    Next
 
   Next
 
  EndIf
 
 EndIf
 
 ;return the result
 $dummy=$MOAN,Split(SubStr($MOAN,2))
 $MOAN=$dummy[Len($MOAN)>1]
 
EndFunction
;!
;!
; end MOAN
this I mean.
for proper explanation see the difference between the winning code and the previous ones.
it's actually too messy with the comments to see where what looping do but looking the golf-codes you see immediately the difference [Wink]

will explain properly, if you still can't see it [Razz]
_________________________
!

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