PROGRAMMER's CHALLENGE

Volume Number: 18 (2002)
Issue Number: 10
Column Tag: PROGRAMMER's CHALLENGE

PROGRAMMER's CHALLENGE

by Bob Boonstra

Area

As those of you who are regular readers know, the Programmer's Challenge problems have become more difficult over time. Just as all scientific discoveries worth making had been made by the mid-twentieth century, so it is that all simple Challenge problems have been posed and solved by this time. Then again, as they say, maybe not. This month's problem is borrowed from http://www.polymathlove.com/, where Gary Smith posts software he uses in teaching mathematics to elementary and middle school students. One of his programs is called Area Puzzles, where students create rectangles with specified areas to cover a grid subject to certain constraints.

The prototype for the code you should write is:

```void Area(
const short *cells,
/* rectangle to be covered with smaller rectangles */
/* index [row][col] as cells[row*rectWidth + col[ */
/* value N>0 means this cell must be covered by a rectangle of area N */
short rectWidth,
short rectHeight,
Rect yourRects[]
);```

Your Area routine will be called with a rectangle of cells of width rectWidth and height rectHeight. Your task is to create a set of smaller rectangles (yourRect) that cover these cells. In doing so, you need to satisfy some constraints. Certain of the cells will have a nonzero value, and those cells must be covered by a rectangle with an area equal to that value. As an example, if the input cells were configured as follows ...

```   0  0  3  0  6  0  0  0  0  8
0  6  0  0  0  0  0  0  0  0
0  0  0  0  0  0  4  0  0  0
0  0  3  0  0  0  0  0  0  0
0  0  0  0  0  0  0  0  0  0
6  0  0  0  0  0  0  0 15  0
0  0  0  0  0  0  0  0  0  0
0 10  0  0 24  0  0  4  0  0
0  0  0  0  0  0  0  0  0  0
0  0  0  4  0  0  4  0  0  3```

... you might create a set of rectangles like this, where each cell is shown with the number of the rectangle including that cell.

```   1  1  1  2  2  2  3  3  3  3
4  4  5  2  2  2  3  3  3  3
4  4  5  6  6  6  6  7  7  7
4  4  5  8  8  8  8  7  7  7
9 10 10  8  8  8  8  7  7  7
9 10 10  8  8  8  8  7  7  7
9 10 10  8  8  8  8  7  7  7
9 10 10  8  8  8  8 13 13 14
9 10 10  8  8  8  8 13 13 14
9 11 11 11 11 12 12 12 12 14```

You should return the rectangles that cover the cell array and satisfy the constraints as yourRects. Each cell may be included in only one rectangle. If the cell has a nonzero value when Area is called, it must be included in a rectangle with an area equal to that value. Memory for the rectangles you create will be allocated for you, and there will be as many of those rectangles as there are nonzero values in the cells array. Any solution that covers the entire cells array and satisfies the constraints will be considered correct.

Scoring will be based on execution time - the winner will be the solution that correctly solves the puzzles with the smallest execution time.

This will be a native PowerPC Carbon C++ Challenge, using the Metrowerks CodeWarrior Pro 7.0 development environment. Please be certain that your code is carbonized, as I may evaluate this Challenge using Mac OS X. Also, when submitting you solution, please include the project file and the code you used to test your solution. Occasionally I receive a solution that will not compile and, while I always try to correct these problems, it is easier to do so if I have your entire project available.

Winner of the July, 2002 Challenge

Congratulations to Alan Hart (United Kingdom) for winning the July One Time Pad Challenge. Recall that this Challenge required readers to decrypt a sequence of messages using a "one time pad". I place the term in quotation marks because the pad was neither "one time", as it was used multiple times, nor was it random, as a true one-time pad would be. Contestants had the advantage of possessing a dictionary of all the possible words in the communication.

Alan's solution tries each possible offset until the decoding attempt results in a sequence of words found in the dictionary. The speed of Alan's solution is due in part to his decision to test the decoding of the first four characters of the message for each offset against the dictionary before proceeding with the rest of the decoding. Another factor is Alan's reuse (with acknowledgement) of ideas from Ernst Munter's solution to the PlayFair Challenge, specifically the dictionary indexing approach. That approach creates an index for each word based on the first three characters that points to the first word in the dictionary beginning with those three letters. I'm pleased to see past Challenge code reused successfully.

Ernst Munter's second place entry also uses a brute force method. His approach is to select a possible offset from the pad, decrypt the message using that offset, verify that the decrypted message contains only words from the dictionary, and repeat with a new offset until successful. Ernst's solution also uses a modified version of the SpellTree dictionary class he developed for the PlayFair Challenge.

Jonny Taylor's third-place solution also examined the first three characters of the decoded message to determine whether an offset was promising enough to continue decoding. As noted by others, because the message may contain special characters not found in the dictionary, offsets rejected by this approach must be revisited to skip potential special characters if the message is not successfully decoded. Moses Hall takes a different approach, creating a finite state machine encoding the dictionary. Rounding out the remainder of the five top-scoring entries, Jan Schotsman used the Altivec programming model and reports achieving a 5% increase in speed over the non-vectorized version.

The table below lists, for each of the solutions submitted, the number of test cases processed correctly, the execution time in seconds, the bonus awarded for code clarity and commentary, and the total score for each solution. It also lists the programming language of each entry. As usual, the number in parentheses after the entrant's name is the total number of Challenge points earned in all Challenges prior to this one.

```
Name                 Cases     Time   Bonus   Score   Lang
Correct   (secs)
Alan Hart (39)        20       0.73    25%    5469.59   C++
Ernst Munter (872)    20       1.30    25%    9721.75   C++
Jonny Taylor (83)     20       1.67    25%   12499.44   C++
Moses Hall            20       2.54    15%   21572.92   C
Jan Schotsman (16)    20       3.05    5%    28959.52   C++
Tom Saxton (230)      20       3.08    5%    29268.66   C++
Damien Bobillot       15       12.11   15%  102918.96   C```

Top Contestants ...

Listed here are the Top Contestants for the Programmer's Challenge, including everyone who has accumulated 20 or more points during the past two years. The numbers below include points awarded over the 24 most recent contests, including points earned by this month's entrants.

```
Rank    Name                Points      Wins     Total
(24 mo)    (24 mo)   Points
1.   Munter, Ernst         251        8         882
2.   Saxton, Tom            65        2         230
3.   Taylor, Jonathan       64        2          90
4.   Stenger, Allen         53        1         118
5.   Wihlborg, Claes        40        2          49
6.   Hart, Alan             34        1          59
7.   Rieken, Willeke        22        1         134
8.   Landsbert, Robin       22        1          22
9.   Gregg, Xan             20        1         140
10.   Mallett, Jeff         20        1         114
11.   Cooper, Tony          20        1          20
12.   Truskier, Peter       20        1          20```

Here is Alan's winning One Time Pad solution.

Alan Hart

```/******************************************\
Problem definition:
----------------
Decode multiple encrypted messages created using a known one time pad.
Each message is encrypted using an unknown offset in the one time pad.
Each character in the encrypted message is the sum of the corresponding  clear text
The sum is adjusted to remain in the valid character set range.
The character set is 62 upper/lower case alpha-numerics
that appear in words in a case-insensitive dictionary, plus 33 other punctuation and special
characters

("delimiters") that can appear in any locations between words.

Total time is to be minimized.

Assumptions:
-----------
We cannot make any assumptions about the number of delimiter characters that
may preceed the message or separate the words within it. In an ulikely extreme case
the message could be a sea of delimiters with a few short words distributed
anywhere within it. It is assumed that the test cases will not be pathological, and the
majority of characters in the message will form dictionary words. In particular, the
solution is optimized for messages with no leading delimiters before the first
dictionary word. It decrypts messges with leading delimiters during a second scan

Solution Summary:
-----------------
The external interface calls are passed to a Decoder class which does the work.

The gDecoder instance is dynamically assigned by InitOneTimePad () and allocates
a fixed sze array of 256 KBytes for the main dictionary index. Further index Branch
records are allocated dynamically during indexing.
This adds a further 100KBytes to the space required in the case of the dictionry
supplied with the test data.
The solution should fit comfortably in less than 500 KBytes heap space not
including the dictionary and message strings.

The decoder creates a small static lookup table containing two concatenated copies
of the character set to allow for wrap-around when subtracting the pad and cipher
characters, allowing a simple lookup for decoding, and avoiding the need for range
limiting.

Decoding is done by trying each possible pad offset in turn until the decode yields a
sequence of words that are found in the dictionary.

During the first pass candidate pad offsets are found by testing the first 4 characters
at each pad offset with the first 4 message characters. If this fails all pad offsets are
retested on the whole message in case the first word does not start at the first
character of the message. Decoding with each candidate pad is aborted if any
invalid sequence of consecutive dictionary characters is detected or the end of the

The validity of a character sequence is tested in three stages:

1. A sequence of three or more characters must have a "header" index value
matched by one or more dictionary words.
A shorter word must have an index value that matches a bit map of 1 and 2
character words.

2. Characters following a valid header index must form 4-character sequences that
exist somewhere in the dictionary.

3. Finally the word is compared with the dictionary entries using a case insensitive
character match and length comparison.

The dictionary index uses a 32 character (5 bit) enumeration to allow quick
calculation of compact indices, and to enable bit mapping in a single 32 bit word.
The 10 numeric characters are enumerated using 1 to 5, with pairs of digits sharing
the same index value. 6 to 31 enumerate the alphabetic characters, ignoring case.
Zero is used to denote any non-dictionary character.
This enumeration means that words in the supplied dictionary containing numerals
in the indexed characters may not be in correct index order. To avoid having to re-
sort the dictionary this is handled in the index building and searching procedures.

This mapping and indexing system allows a quick confidence check to be carried
out during decoding so that non-indexed final dictionary searching is only done on
longer words, and only when the word is likely to exist.

Words of one or two characters are recorded in a 32 x 32 bit map for a fast lookup.
The index for a word of three or more characters is calculated by concatenating the
index values of the first three characters.
The index selects one of an array of 32x32x32 (32K) Index records used for initial
and final validation of decoded words.
If the Index value is the header for words longer than three characters it has a
pointer to a dynamically allocated 32 entry lookup table. Each entry in the table
points to the first word in the dictionary whose 4th character matches
one character index value.
The Index record also has a bit map of the valid fourth character indices that can
follow this sequence when it appears at character positions 3, 6, 9 ... in the body of
any word in the dictionary.

Optimizations applied included using unsigned types to remove compiled sign
extend instructions, longs to remove compiled byte mask instructions, and the
addition of the first pass decoder to limit the tested pad offsets to those yielding
valid indices for the first 4 message characters. Instruction sequencing was also

Acknowledgement
----------------
The dictionary indexing system uses some ideas gleaned by revisiting
Ernst Munter's winning solution to the 1999 Playfair challenge.

\******************************************/
//   use unsigned types wherever possible to minimize the insertion of sign extend
// instructions by the compiler
typedef   unsigned char   uchar;
typedef   unsigned long   ulong;
typedef   unsigned long   blong;   //   used instead of bool to avoid character masking instructions

static const ulong IndexOffset [128] = {
//   lookup table to convert character codes to index offset values
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 0, 0, 0, 0, 0, 0,
0, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 0, 0, 0, 0, 0,
0, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,
21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 0, 0, 0, 0, 0
};
IndexValue
static inline ulong
IndexValue (const uchar* inWord) {
//   Return the index for the first three characters of a word
ulong   index = IndexOffset [*(inWord ++)];
index = (index << 5) | IndexOffset [*(inWord ++)];
return (index << 5) | IndexOffset [*inWord];
}
struct Branch
struct Branch {
const uchar**   fFirstWord;
const uchar**   fLastWord;
Branch () { fFirstWord = fLastWord = NULL; }

blong   ValidateWord (uchar* inWord, ulong inWordLength) {
//   Compare inWord with each word in this branch
//   The indices are known to match, so inWord already points to the 4th character of
// the test word
//   Note that the ambiguous indexing of numeric characters means it is possible to
// return a false positive.
//   This is not considered a problem, as we are only trying to verify that the one time
// pad is correctly aligned to produce a string of credible words. However, it means
// that shorter dictionary words can appear within within the indexed range, and
// must be ignored.
const   uchar**   wordPtr =fFirstWord;
do {
//   3 or more characters in this dictionary word
const uchar*   w1 = *wordPtr + 4;
uchar*      w2 = inWord;
long         difference =  0;
long         len = inWordLength;
while ( ! difference && *w1) {
//   compare the words until the end of the dictionary word
//   converting upper case characters in inWord to lower case
difference = (*(w1++) - (*(w2++) | 0x20));
len --;
}
if (difference == 0 && len == 0) return true;
// words match
if (difference > 0) return false;
//   this and subsequent words are greater than inWord
}
} while (wordPtr ++ < fLastWord);
return false;   //   no match found
}
};

class    Index
class    Index {
//   Dictionary index entry for a three-character sequence
public:
//   Data encapsulation is not used, so that the decoder can access Index members
// directly for higher performance
Branch   *fBranches;
//   Dynamically allocated list of 32 pointers to words that start with this index
ulong      fMap;
//   Map of valid fourth character indices that can follow this index in the body
// of a word
//   fMap bit 0 is used to register a valid three letter word for this index
Index () { fBranches = NULL; fMap = 0; }

~Index () { delete [] fBranches; }

ulong      //   Return the number of words registered for this index value
Register (
const uchar** inWordList,   // Pointer to the first word to register
ulong inIndex,            //   The index value for words to register
const uchar** inLastWord,   // The last word in the dictionary, for
//range checking
Index* inIndexArray
//   The array if Index records, used to registerword body sequences
) {
//   This is the dictionary indexing procedure
//   - Registers the existence of one or more 3 character words for this index in fMap
// bit zero
//   - If there are words of 4 or more characters with this index value, allocates a
// Branch array   and records the first and last words of the list for each 4th character.
//   - Registers the existence of each 4-letter sequence in the body of each word in the
// fMap for its index
const uchar**   wordPtr = inWordList;
ulong         index = inIndex;
const uchar*   word;
Branch*      branch = NULL;
do {
uchar   c = IndexOffset [*((*wordPtr) + 3)];
if (c) {
//   4 or more characters
if (fBranches == NULL) {
//   allocate a new branch list to index words on the 4th character
fBranches = new Branch [32];
if (fBranches == 0)
return 0;   //   bail out and signal allocation failure
}
//   record the start and end words in each branch
if (branch != fBranches + c) {   // end of previous branch
if (branch)
//   update the last word pointer for the old branch
branch->fLastWord = wordPtr - 1;
//   move to the next branch
branch = fBranches + c;
if (branch->fFirstWord == NULL)
//   this is the first word to be registered in this branch
//   insert the first word pointer for this branch
branch->fFirstWord = wordPtr;
}
//   register the remaining map bits for the body of this word
word = (*wordPtr) + 3;   //   skip the index
while (*word && *(word+1) && *(word+2)) {
//   while there are three or more characters left
//   get the 4th character index
c = IndexOffset [*(word + 3)];
if (c == 0) break;   // no 4th character
//   register the 4th character in the index bit map
inIndexArray [ IndexValue (word) ].fMap |= ( 1 <<  c);
word += 3;
}
} else
//   register the 3 character word in bit 0 of the index map
fMap |= 1;
wordPtr ++;   //   next word

//   until end of dictionary or index value changes
} while (wordPtr < inLastWord &&
index == IndexValue (*wordPtr));

if (branch)   //   update the last branch
branch->fLastWord = wordPtr - 1;
//   return the number of words registered
return wordPtr - inWordList;
}
blong   ValidateWord (uchar* inWord, ulong inWordLength)
{
//   The dictionary lookup procedure.
//   - Returns true if the word exists in the dictionary
if (inWordLength == 3)
//   3 character word. Check map bit 0
return (fMap & 0x01);
else if (fBranches) {
//   Compare the 4th and subsequent characters with the words in the appropriate
// branch
Branch*   branch = fBranches + IndexOffset [*(inWord + 3)];
if (branch->fFirstWord)
return branch->ValidateWord (inWord + 4, inWordLength - 4);
}
return false;
}
};
class Decoder
class    Decoder {
private:
//   pointer to the current first pad character
//   pointer to the last pad character to try
ulong         fMessageLength;      //   length of the encrypted string
//   Dictionary infomation
Index      fIndexArray [ 32*32*32 ];   //   the dictionary index array
ulong         fShortWordMap [32];
//   a bit map for one and two character words
//   The decoder table
ulong         fDecodeTable [190];
//   lookup table to convert a pair of cipher/pad characters to a clear character
public
{
//   Constructor initializes the data members
//   The dictionary index is built separately to allow Branch allocation failure to be
//  handled gracefully

//   Fill in the decoder table with two concatenated copies of the character set
int   c;
ulong*   t = fDecodeTable;
for (c = 0x20; c < 0x7f; c ++, t ++)
*t = *(t + 0x5f) = c;

//   Clear the short word map
for (c = 0; c < 32; c ++)
fShortWordMap [c] = 0;
}

blong      IndexDictionary (const uchar** inDictionary,
ulong inNumWords)
{
//   Build the dictionary index and short word map
//   Return false if Branch allocation falis
const uchar**   wordPtr = inDictionary;
const uchar**   lastWord = inDictionary + inNumWords;
ulong      numWords;
do {
//   Process the next index value
ulong      index = *(ulong*)(*wordPtr);
numWords = 1;
if ((index & 0x0ff0000) == 0)
//   Register a 1 character word in short word map zero
*fShortWordMap |= (1 <<
IndexOffset [(index >> 24) & 0xff]);
else if ((index & 0x0ff00) == 0)
//   Register a 2 character word in the appropriate short word map
fShortWordMap[ IndexOffset[(index >> 24) & 0xff] ]
|= (1 << IndexOffset [(index >> 16) & 0xff]);
else {
//   3 or more characters
//   Pass the word list to the appropriate Index record for registration
index = IndexValue (*wordPtr);
numWords = fIndexArray [index].Register (wordPtr, index,
lastWord, fIndexArray);
if (numWords == 0)
//   branch list allocation failure - bail out
break;
}
//   Next word list
wordPtr += numWords;
} while (wordPtr < lastWord);

return (numWords > 0);
}

uchar* outDecryptedMessage, ulong *outOffset)
{
//   The main routine called to decode messages

//   Use trial and error to find a pad offset that successfully decodes the message
//   Return the offset found in *outOffset

//   Firat Pass
//   Optimized search for candidate pad offsets that decode a valid word index at the
// first encrypted character
//   Build lookup tables to decode each of the first 4 message characters to its index
// value for any pad character
//   Shift the pad through a 4-character buffer and apply this to the 4 message
// characters

ulong         c0, c1, c2;
ulong*       mapPtr;
blong         validOffset;
ulong         map, i;
const uchar*   cipher = inEncryptedMessage;

//   Measure the encrypted message length
while (*(++cipher)) {;}
fMessageLength = cipher - inEncryptedMessage;

cipher = inEncryptedMessage;
for (map = 0; map < 4; map ++, cipher ++) {
//   create the decode table for the next cipher character
//   clear the entries for invalid pad characters
*(mapPtr + 0x7f) = 0;
i = 0x20; while (i --) { *(mapPtr++) = 0; }
//   set the decoded index values for each valid pad character
//   calculate the first offset in the decode table for this cipher character
ulong*   c = fDecodeTable + 0x3f + *cipher;
i = 0x5f; while (i --) { *(mapPtr++) = I
ndexOffset [*(c --)]; }
}
//   Start at the beginning of the one time pad.
//   Decode these 4 characters with each pad offset and look for a valid word or index

validOffset = false;
//   prime a sequence of 4 characters with the first 3 valid pad characters
for (i = 0; i < 3; i ++) {
if (*pad == 0) return;   //   Abort if the pad is less than 4 characters
}
}
do {
//   Shift the next valid pad character into the set

//   1st character decodes to a dictionary character
if ( (c1 = padMapArray[1] [(padBuffer >> 16) & 0xff] ) ) {
//   2nd character decodes to a dictionary character
if ( (c2 = padMapArray [2] [(padBuffer >> 8) & 0xff]) ) {
//   select the appropriate Index record for the 3 characters
Index*   header =fIndexArray + ((((c0 << 5) | c1) << 5) |
c2);
//   decode the 4th character
//   check that the Branch index exists for the 4th character
else
//   check for a valid 3 character word
} else
//   check for a valid 2 character word
validOffset = fShortWordMap [c0] & (1 << c1);
} else
//   check for a valid single character word
validOffset = (*fShortWordMap) & (1 << c0);

if (validOffset) {
//   This pad offset decodes a valid word or index
//   try to decode the whole message using this candidate pad
outDecryptedMessage);
}
}
do {
else
//   We've run out of pad characters - end of pass 1
goto SecondPass;

} while ( ! validOffset);
if ( ! validOffset ) {
SecondPass:
//   Second Pass
//   The search for the first index may have failed due to leading delimiters
//   Try to decode the message using every pad offset in turn
do {
outDecryptedMessage);
} while ( ! validOffset && *(fFirstPadChar +
fMessageLength));
}
//   return the offset
}
uchar* outDecryptedMessage)
{
//   Called by FindPadOffset() with fFirstPadChar pointing to the start of a candidate
//   Attempt to decode the message using this pad, and return success/failure

const uchar*   cipher;   //   pointer to the next encrypted character to decode
uchar*      clear;   //   pointer to the next clear character to decode
ulong         index;   //   index value of current word
const ulong*   origin = fDecodeTable + 0x5f;
//   pointer to the origin in the DecodeTable
uchar*      word;   //   pointer to start of current word being processed
Index      *body, *header;   //   pointers to the Index records for the
//   current word
ulong         c0, c1, c2;
//   index values of the first three characters of teh current word
ulong         state = 0;   //   controls progress of the word decode process

clear = outDecryptedMessage;
cipher = inEncryptedMessage;

do {
//   for each character in the message

else goto Exit;   //   end of pad
}
//   decode the character
*clear = *(origin + *cipher - *pad);
switch (state) {
case 0:   //   looking for 1st character of a word
if ( (c0 = IndexOffset [*clear]) ) {
word = clear;   //   1st character of a word
state = 1;
}
break;
case 1:   //   looking for 2nd character of a word
if ( (c1 = IndexOffset [*clear]) ) state = 2;
//   2nd dictionary char
else if ((*fShortWordMap) & (1 << c0))
//   valid 1 character word
state = 0;
else goto Exit;
break;
case 2:   //   looking for 3rd character of a word
if ( (c2 = IndexOffset [*clear]) ) {
header =fIndexArray + ((((c0 << 5) | c1) << 5) | c2);
state = 3;   //   3rd dictionary char
} else if (fShortWordMap [c0] & (1 << c1))
//   valid 2 character word
state = 0;
else goto Exit;
break;
case 3:   //   looking for 4th character of a word
if ( (c0 = IndexOffset [*clear]) ) {
index = c0;   //   valid 4th dictionary char
body = NULL;
state = 4;   //   check body sequences
} else goto Exit;
} else if (header->fMap & 0x01)
//   valid 3 character word
state = 0;
else goto Exit;
break;
case 4:
if ( (c0 = IndexOffset [*clear]) ) {
if (body == NULL) {
index = (index << 5) | c0; // accumulate the body index
if (index > 1024)
//   third body index character. select the Index record
body = fIndexArray + index;
} else {   //   look up this character in the current body Index record
if (body->fMap & (1 << c0)) {
//   valid sequence - start building the next body index
index = c0;
body = NULL;
} else goto Exit;
}
} else {
//   end of the word, confirm it is in the dictionary
if (header->ValidateWord (word, clear - word))
state = 0;
else goto Exit;
}
default:
break;
}
clear ++;
} while (*(++cipher));

Exit:
*clear = 0;   //   terminate the decoded string
return ((*cipher) == 0);   //   successful if we reached the end of the
//   message
}

} *gDecoder;   //   global pointer to a dynamically allocated instance
//   Create the decoder
gDecoder = new Decoder ((const uchar*) oneTimePad);
if ( gDecoder) {
//   Index the dictionary
if ( ! gDecoder->IndexDictionary ((const uchar**) dictionary,
(ulong) numDictionaryWords)) {
//   Allocation failure
delete gDecoder;
gDecoder = NULL;
}
}
}
DecryptMessage
void DecryptMessage(const char *encryptedMessage, char *decryptedMessage, long *offset) {
if (gDecoder)
(uchar*) decryptedMessage, (ulong*)offset);
}
delete gDecoder;
}```

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Vivaldi 1.0.118.19 - Lightweight browser...
Vivaldi browser. In 1994, two programmers started working on a web browser. Our idea was to make a really fast browser, capable of running on limited hardware, keeping in mind that users are... Read more
Stacks 2.6.11 - New way to create pages...
Stacks is a new way to create pages in RapidWeaver. It's a plugin designed to combine drag-and-drop simplicity with the power of fluid layout. Features: Fluid Layout: Stacks lets you build pages... Read more
xScope 4.1.3 - Onscreen graphic measurem...
xScope is powerful set of tools that are ideal for measuring, inspecting, and testing on-screen graphics and layouts. Its tools float above your desktop windows and can be accessed via a toolbar,... Read more
Cyberduck 4.7 - FTP and SFTP browser. (F...
Cyberduck is a robust FTP/FTP-TLS/SFTP browser for the Mac whose lack of visual clutter and cleverly intuitive features make it easy to use. Support for external editors and system technologies such... Read more
Labels & Addresses 1.7 - Powerful la...
Labels & Addresses is a home and office tool for printing all sorts of labels, envelopes, inventory labels, and price tags. Merge-printing capability makes the program a great tool for holiday... Read more
teleport 1.2.1 - Use one mouse/keyboard...
teleport is a simple utility to let you use one single mouse and keyboard to control several of your Macs. Simply reach the edge of your screen, and your mouse teleports to your other Mac! The... Read more
Apple iMovie 10.0.8 - Edit personal vide...
With an all-new design, Apple iMovie lets you enjoy your videos like never before. Browse your clips more easily, instantly share your favorite moments, and create beautiful HD movies and Hollywood-... Read more

Latest Forum Discussions

Use Batting Average and the Apple Watch...
Batting Average, by Pixolini, is designed to help you manage your statistics. Every time you go to bat, you can use your Apple Watch to track  your swings, strikes, and hits. [Read more] | Read more »
Celebrate Studio Pango's 3rd Annive...
It is time to party, Pangoland pals! Studio Pango is celebrating their 3rd birthday and their gift to you is a new update to Pangoland. [Read more] | Read more »
Become the World's Most Important D...
Must Deliver, by cherrypick games, is a top-down endless-runner witha healthy dose of the living dead. [Read more] | Read more »
SoundHound + LiveLyrics is Making its De...
SoundHound Inc. has announced that SoundHound + LiveLyrics, will be one of the first third-party apps to hit the Apple Watch. With  SoundHound you'll be able to tap on your watch and have the app recognize the music you are listening to, then have... | Read more »
Adobe Joins the Apple Watch Lineup With...
A whole tidal wave of apps are headed for the Apple Watch, and Adobe has joined in with 3 new ways to enhance your creativity and collaborate with others. The watch apps pair with iPad/iPhone apps to give you total control over your Adobe projects... | Read more »
Z Steel Soldiers, Sequel to Kavcom'...
Kavcom has released Z Steel Soldiers, which continues the story of the comedic RTS originally created by the Bitmap Brothers. [Read more] | Read more »
Seene Lets You Create 3D Images With You...
Seene, by Obvious Engineering, is a 3D capture app that's meant to allow you to create visually stunning 3D images with a tap of your finger, and then share them as a 3D photo, video or gif. [Read more] | Read more »
Lost Within - Tips, Tricks, and Strategi...
Have you just downloaded Lost Within and are you in need of a guiding hand? While it’s not the toughest of games out there you might still want some helpful tips to get you started. [Read more] | Read more »
The Petcube Camera is a device that lets you use live video to check in on your pet, talk to them, and play with them using a laser pointer - all while you're away. And the Petcube app is coming to the Apple Watch, so you'll be able to hang out with... | Read more »
Now You Can Manage Your Line2 Calls With...
You'll be able to get your Line2 cloud phone service on the Apple Watch very soon. The watch app can send and receive messages using hands-free voice dictation, or by selecting from a list of provided responses. [Read more] | Read more »

Price Scanner via MacPrices.net

Intel Compute Stick: A New Mini-Computing For...
The Intel Compute Stick, a new pocket-sized computer based on a quad-core Intel Atom processor running Windows 8.1 with Bing, is available now through Intel Authorized Dealers across much of the... Read more
Heal to Launch First One-Touch House Call Doc...
Santa Monica, California based Heal, a pioneer in on-demand personal health care services — will offer the first one-touch, on-demand house call doctor app for the Apple Watch. Heal’s Watch app,... Read more
Mac Notebooks: Avoiding MagSafe Power Adapter...
Apple Support says proper usage, care, and maintenance of Your Mac notebook’s MagSafe power adapter can substantially increase the the adapter’s service life. Of course, MagSafe itself is an Apple... Read more
12″ Retina MacBook In Shootout With Air And P...
BareFeats’ rob-ART morgan has posted another comparison of the 12″ MacBook with other Mac laptops, noting that the general goodness of all Mac laptops can make which one to purchase a tough decision... Read more
FileMaker Go for iPad and iPhone: Over 1.5 Mi...
FileMaker has announced that its FileMaker Go for iPad and iPhone app has surpassed 1.5 million downloads from the iTunes App Store. The milestone confirms the continued popularity of the FileMaker... Read more
Sale! 13-inch 2.7GHz Retina MacBook Pro for \$...
Best Buy has the new 2015 13″ 2.7GHz/128GB Retina MacBook Pro on sale for \$1099 – \$200 off MSRP. Choose free shipping or free local store pickup (if available). Price for online orders only, in-... Read more
Minimalist MacBook Confirms Death of Steve Jo...
ReadWrite’s Adriana Lee has posted a eulogy for the “Digital Hub” concept Steve Jobs first proposed back in 2001, declaring the new 12-inch MacBook with its single, over-subscribed USB-C port to be... Read more
13-inch 2.7GHz Retina MacBook Pro for \$1234 w...
Adorama has the 13″ 2.7GHz/128GB Retina MacBook Pro in stock for \$1234.99 (\$65 off MSRP) including free shipping plus a free LG external DVD/CD optical drive. Adorama charges sales tax in NY & NJ... Read more
13-inch 2.5GHz MacBook Pro available for \$999...
Adorama has the 13-inch 2.5GHz MacBook Pro on sale for \$999 including free shipping plus NY & NJ sales tax only. Their price is \$100 off MSRP. Read more
Save up to \$600 with Apple refurbished Mac Pr...
The Apple Store is offering Apple Certified Refurbished Mac Pros for up to \$600 off the cost of new models. An Apple one-year warranty is included with each Mac Pro, and shipping is free. The... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
*Apple* Support Technician IV - Jack Henry a...
Job Description Jack Henry & Associates is seeking an Apple Support Technician. This position while acting independently, ensures the proper day-to-day control of Read more
*Apple* Client Systems Solution Specialist -...
…drive revenue and profit in assigned sales segment and/or region specific to the Apple brand and product sets. This person will work directly with CDW Account Managers Read more
*Apple* Software Support - Casper (Can work...
…experience . Full knowledge of Mac OS X and prior . Mac OSX / Server . Apple Remote Desktop . Process Documentation . Ability to prioritize multiple tasks in a fast pace Read more
*Apple* Software Support - Xerox Corporation...
…Imaging experience Full knowledge of Mac OS X and prior Mac OSX / Server Apple Remote Desktop Process Documentation Ability to prioritize multiple tasks in a fast pace Read more