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Feb 96 Challenge
Volume Number:12
Issue Number:2
Column Tag:Programmer’s Challenge

Programmer’s Challenge

By Bob Boonstra, Westford, Massachusetts

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Intersecting Rectangles

The Challenge this month is to write a routine that will accept a list of rectangles and calculate a result based on the intersections of those rectangles. Specifically, your code will return a list of non-overlapping rectangles that contain all points enclosed by an odd (or even) number of the input rectangles. The prototype for the code you should write is:

void RectangleIntersections(
 const Rect inputRects[], /* list if input rectangles */
 const long numRectsIn,   /* number of inputRects */
 Rect outputRects[], /* preallocated storage for output */
 long *numRectsOut,/* number of outputRects returned */
 const Boolean oddParity  /* see text for explanation */
);

The parameter oddParity indicates whether you are to return rectangles containing points enclosed by an odd number of the numRectsIn inputRects rectangles (oddParity==true) or by an even (nonzero) number of rectangles (oddParity==false). Sufficient storage for the output will be preallocated for you and pointed to by outputRects.

As an example, if you were given these inputRects:

 {0,10,20,30}, {5,15,20,30}

and oddParity were true, you might return the following list of outputRects:

 {0,10,5,15}, {0,15,5,30}, {5,10,15,20}

It would also be correct to return a result that combined the first of these rectangles with either of the other two. If oddParity were false, you would return the following list for the example input:

 {5,15,20,30}

The outputRects must be non-empty and non-overlapping. In the example, it would be incorrect to return the following for the odd parity case:

 {0,10,5,30} {0,10,20,15}

The outputRects you generate must also be maximal, in the sense that each edge of each of the outputRects should pass through a vertex of one of the inputRects. That is, for example, I don’t want you to return a 1¥1 rectangle representing each point enclosed in the desired number of inputRects. Before returning, set *numRectsOut to indicate the number of outputRects you generated.

If you need auxiliary storage, you may allocate any reasonable amount within your code using toolbox routines or malloc, but you must deallocate that storage before returning. (No memory leaks! - I’ll be calling your code many times.)

This native PowerPC Challenge will be scored using the latest Metrowerks compiler, with the winner determined by execution time. If you have any questions, or would like some test data for your code, please send me e-mail at one of the Programmer’s Challenge addresses, or directly to bob_boonstra@mactech.com. Test data will also be sent to the Programmer’s Challenge mailing list, which you can join by sending a message to autoshare@mactech.com with the SUBJECT line “sub challenge YourName”, substituting your real name for YourName.

Two Months Ago Winner

Eight of the 13 solutions submitted for the Find Again And Again Challenge worked correctly. Congratulations to Gustav Larsson (Mountain View, CA) for submitting an entry that was significantly faster than the others. The problem was to write a text search engine optimized to operate repeatedly on the same block of text. A variety of optimization techniques were represented in the solutions, a couple of which are highlighted in the table of results below. Several people optimized for the case where the same word was repeatedly searched for. Some of my tests included this case, and those results are in the columns headed “repeat.” The “random” columns shows results for tests that searched for random occurrences of random words. Each of the tests were run under conditions where only 64KB of auxiliary storage was available, and where much more memory was available. These conditions were weighted 20% and 80% respectively in calculating the total time, since the problem statement promised that ample memory would usually be provided. You can see that Gustav’s solution performed reasonably well when memory was scarce, and very well when memory was plentiful.

Gustav’s solution hashes as many words of the input text as possible in the initialization routine. He uses the Boyer-Moore-Horspool algorithm to find words in any text that was not parsed during initialization. Other features of the approach are described in the well-commented code.

Here are the times and code sizes for entries that passed by tests. Numbers in parentheses after a person’s name indicate that person’s cumulative point total for all previous Challenges, not including this one.

64K Memory >>64K Memory code

Name repeat random repeat random time size

Gustav Larsson (67) 1814 3773 62 111 1255 3584

Tom Saxton 46 16400 197 459 3814 2000

Xan Gregg (81) 27 2907 1316 2835 3907 1664

Kevin Cutts (46) 1760 3234 1760 2809 4654 1600

Joseph Ku 8856 14570 121 509 5189 1584

David Cary 60 22665 499 1000 5745 2124

Eric Lengyel (40) 34 10221 29 4697 5831 1188

Ernst Munter (110) 2036 2053 2287 4603 6330 2976

Top Contestants of All time

Here are the Top Contestants for the Programmer’s Challenges to date, including everyone who has accumulated more than 20 points. The numbers below include points awarded for this month’s entrants.

Rank Name Points Rank Name Points

1. [Name deleted] 176 11. Mallett, Jeff 44

2. Munter, Ernst 110 12. Kasparian, Raffi 42

3. Gregg, Xan 88 13. Vineyard, Jeremy 42

4. Larsson, Gustav 87 14. Lengyel, Eric 40

5. Karsh, Bill 80 15. Darrah, Dave 31

6. Stenger, Allen 65 16. Landry, Larry 29

7. Riha, Stepan 51 17. Elwertowski, Tom 24

8. Cutts, Kevin 50 18. Lee, Johnny 22

9. Goebel, James 49 19. Noll, Robert 22

10. Nepsund, Ronald 47

There are three ways to earn points: (1) scoring in the top 5 of any Challenge, (2) being the first person to find a bug in a published winning solution or, (3) being the first person to suggest a Challenge that I use. The points you can win are:

1st place 20 points 5th place 2 points

2nd place 10 points finding bug 2 points

3rd place 7 points suggesting Challenge 2 points

4th place 4 points

Here is Gustav’s winning solution:

Find Again and Again

Copyright © 1995 Gustav Larsson

Constants & Types
#define ALPHABET_SIZE 256
#define ALLOC_SIZE(n) ((n+3) & -4L) /* next multiple of 4 */
#define HASH_BUCKETS 1024           /* must be power of 2 */
#define HASH_MASK (HASH_BUCKETS - 1)
#define NO_NULL_CHAR 'A'
#define NULL 0

typedef unsigned char  uchar;
typedef unsigned short ushort;
typedef unsigned long  ulong;

typedef struct Word Word;
typedef struct Occurrence Occurrence;
typedef struct Private Private;

/* 
  A block of occurrence positions.  We pack in as many occurrences as possible into 
  a single block, from 3 to 6 depending on textLength.

  The first entry in the block is always used.  The remaining entries are in use if they 
  are not zero.  These facts are used several places to simplify the code.
*/
struct Occurrence {
  Occurrence *next;
  union {
    ushort pos2[6];   /* 2 bytes/occurrence */
    struct {
      ushort lo[4];
      uchar  hi[4];
    } pos3;           /* 3 bytes/occurrence */
    long pos4[3];     /* 4 bytes/occurrence */
  } p;
};

/*
  There is one Word struct for each distinct word.  The word’s length is stored in the 
  top eight bits of the hash value.  There’s no need to store the characters in the word 
  since we can just look at the first occurrence (first entry in Word.first).
*/
struct Word {
  Word        *next;
  ulong       hash;
  Occurrence  *last;
  Occurrence  first;
};

/*
  The structure of our private storage.  The hashCodes[] array serves two purposes: it 
  distinguishes alphanumeric from non-alphanumeric characters, and it provides a 
  non-zero hash code for each alphanumeric character.  The endParsedText field will 
  be -1 if there was enough private memory to parse all the text.  Otherwise, it points to 
  the start of the unparsed text.  nullChar is used by the BMH_Search() function when 
  we must search unparsed text for an occurrence.
*/
struct Private {
  ulong hashCodes [ ALPHABET_SIZE ];
  Word  *hashTable [ HASH_BUCKETS ];
  long  endParsedText;  /* start of parsed text */
  long  posBytes;       /* POS_x_BYTES, below */
  char  nullChar;       /* char not appearing in the text */
  long  heap;           /* start of private heap  */
};

Macros
/*
  These macros simplify access to the occurrence positions stored in an Occurrence 
  struct.  Posbytes is a macro argument that is usually set to private->posBytes.  
  However, you can also use a constant for posbytes, which lets the compiler choose 
  the right case at compile time, producing smaller and faster code.
*/
#define POS_2_BYTES 1   /* word position fits in 2 bytes */
#define POS_3_BYTES 0   /* fits in 3 bytes; usual case */
#define POS_4_BYTES 2   /* fits in 4 bytes */

#define GET_POS(pos,occur,index,posbytes)           \
  {                                                 \
    if ( (posbytes) == POS_3_BYTES )                \
      pos = ((long)(occur)->p.pos3.hi[index] << 16) \
          + (occur)->p.pos3.lo[index];              \
    else if ( (posbytes) == POS_2_BYTES )           \
      pos = (occur)->p.pos2[index];                 \
    else                                            \
      pos = (occur)->p.pos4[index];                 \
  }

#define SET_POS(pos,occur,index,posbytes)       \
  {                                             \
    if ( (posbytes) == POS_3_BYTES )            \
    {                                           \
      (occur)->p.pos3.hi[index] = (pos) >> 16;  \
      (occur)->p.pos3.lo[index] = (pos);        \
    }                                           \
    else if ( (posbytes) == POS_2_BYTES )       \
      (occur)->p.pos2[index] = pos;             \
    else                                        \
      (occur)->p.pos4[index] = pos;             \
  }

InitFind
void InitFind (
  char *textToSearch,
  long textLength,
  void *privateStorage,
  long storageSize
)
{
  Private *private = privateStorage;

  private->endParsedText =
    InitFindBody(
        (uchar *)textToSearch,
        textLength,
        privateStorage,
        (uchar *)privateStorage + storageSize
    );

  if ( private->endParsedText != -1 )
    private->nullChar =
      PickNullChar(
            private,
            (uchar *)textToSearch + private->endParsedText,
            (uchar *)textToSearch + textLength );
  else
    private->nullChar = NO_NULL_CHAR;
}

InitFindBody
/*
  This function does most of the work for InitFind().  The arguments have been recast 
  into a more useful form; uchar and ulong are used a lot so that we don’t have to 
  worry about the sign, especially when indexing private->hashCodes[].

  The return value is the character position when the unparsed text begins (if we run 
  out of private storage), or -1 if all the text was parsed.
*/
static long InitFindBody (
  uchar   *textToSearch,
  long    textLength,
  Private *private,
  uchar   *endPrivateStorage
)
{
  uchar       *alloc, *textPos, *textEnd, *wordStart;
  long        wordLength;
  ulong       hash, code;
  Word        *word;
  Occurrence  *occur;

/*
  Init table of hash codes.  The remaining entries are guaranteed to be initialized to 
  zero.  The hash codes were chosen so that any two codes differ by at least five bits.
  */
  {
    ulong *table = private->hashCodes;  /* reduces typing */

    table['0'] = 0xFFC0;  table['5'] = 0xF492;
    table['1'] = 0xFE07;  table['6'] = 0xF31E;
    table['2'] = 0xF98B;  table['7'] = 0xF2D9;
    table['3'] = 0xF84C;  table['8'] = 0xCF96;
    table['4'] = 0xF555;  table['9'] = 0xCE51;

    table['A'] = 0xC9DD;  table['N'] = 0xA245;
    table['B'] = 0xC81A;  table['O'] = 0x9F0A;
    table['C'] = 0xC503;  table['P'] = 0x9ECD;
    table['D'] = 0xC4C4;  table['Q'] = 0x9941;
    table['E'] = 0xC348;  table['R'] = 0x9886;
    table['F'] = 0xC28F;  table['S'] = 0x959F;
    table['G'] = 0xAF5C;  table['T'] = 0x9458;
    table['H'] = 0xAE9B;  table['U'] = 0x93D4;
    table['I'] = 0xA917;  table['V'] = 0x9213;
    table['J'] = 0xA8D0;  table['W'] = 0x6DD3;
    table['K'] = 0xA5C9;  table['X'] = 0x6C14;
    table['L'] = 0xA40E;  table['Y'] = 0x6B98;
    table['M'] = 0xA382;  table['Z'] = 0x6A5F;

    table['a'] = 0x6746;  table['n'] = 0x3C88;
    table['b'] = 0x6681;  table['o'] = 0x3B04;
    table['c'] = 0x610D;  table['p'] = 0x3AC3;
    table['d'] = 0x60CA;  table['q'] = 0x37DA;
    table['e'] = 0x5D85;  table['r'] = 0x361D;
    table['f'] = 0x5C42;  table['s'] = 0x3191;
    table['g'] = 0x5BCE;  table['t'] = 0x3056;
    table['h'] = 0x5A09;  table['u'] = 0x0D19;
    table['i'] = 0x5710;  table['v'] = 0x0CDE;
    table['j'] = 0x56D7;  table['w'] = 0x0B52;
    table['k'] = 0x515B;  table['x'] = 0x0A95;
    table['l'] = 0x509C;  table['y'] = 0x078C;
    table['m'] = 0x3D4F;  table['z'] = 0x064B;
  }

  /*  Determine the number of bytes needed to store each occurrence position. */
  if ( textLength <= 0x10000L )
    private->posBytes = POS_2_BYTES;
  else if ( textLength <= 0x1000000L )
    private->posBytes = POS_3_BYTES;
  else
    private->posBytes = POS_4_BYTES;

  /* Set up variables to handle allocation of private storage. */
  alloc = (uchar *)&private->heap;

  /* Parse the text */
  textPos = textToSearch;
  textEnd = textPos + textLength;

  while ( textPos != textEnd )
  {
    /* Search for start of word */
    while ( private->hashCodes[*textPos] == 0 )
    {
      textPos++;
      if ( textPos == textEnd )
        return -1;  /* parse all text */
    }
    wordStart = textPos;

    /* Search for end of word; generate hash value too */
    hash = 0;
    while ( textPos != textEnd &&
            (code = private->hashCodes[ *textPos ]) != 0 )
    {
      hash = (hash << 1) ^ code;
      textPos++;
    }
    wordLength = textPos - wordStart;
    hash = (hash & 0xFFFFFF) | (wordLength << 24);

    /*
      Record the occurrence.  First we see if a Word struct exists for this word and 
      whether we need to allocate a new Occurrence struct.
    */
    word = LookupWord(
                private,
                (char *)textToSearch,
                (char *)wordStart,
                wordLength,
                hash );
    if ( word )
    {
      long allocateNewBlock, blockSize, i, pos;

      /*
        This word has occurred before, so it already has a Word struct.  See if there’s 
        room in the last Occurrence block for another entry.  Remember that entry #0 in 
        the Occurrence block is always in use, so we can start checking at entry #1 for a 
        non-zero entry.
      */
      occur = word->last;
      allocateNewBlock = TRUE;
      switch ( private->posBytes )
      {
        case POS_2_BYTES:  blockSize = 6; break;
        case POS_3_BYTES:  blockSize = 4; break;
        case POS_4_BYTES:  blockSize = 3; break;
      }

      for ( i = 1; i < blockSize; i++ )
      {
        GET_POS( pos, occur, i, private->posBytes )
        if ( pos == 0 )
        {
          SET_POS( wordStart - textToSearch, occur, i,
                   private->posBytes )
          allocateNewBlock = FALSE;
          break;
        }
      }

      if ( allocateNewBlock )
      {
        /* Block is full.  Allocate new Occurrence block */
        occur = (Occurrence *) alloc;
        alloc += ALLOC_SIZE( sizeof(Occurrence) );
        if ( alloc >= endPrivateStorage )
          return wordStart-textToSearch; /* out of memory */

        /* Init the new struct and link it to the end of the occurence list. */
        SET_POS( wordStart - textToSearch, occur, 0,
                 private->posBytes )
        word->last->next = occur;
        word->last = occur;
      }
    }
    else
    {
      long i;

/* This is a new word.  Allocate a new Word struct, which contains an Occurrence 
    struct too.  */
      word = (Word *) alloc;
      alloc += ALLOC_SIZE( sizeof(Word) );
      if ( alloc >= endPrivateStorage )
        return wordStart-textToSearch ;  /* out of memory */

      /*  Link it to the start of the Word list, coming off the hash table. */
      word->next = private->hashTable[ hash & HASH_MASK ];
      private->hashTable[ hash & HASH_MASK ] = word;

      /* Init the Word struct */
      word->hash = hash;
      word->last = &word->first;

      /* Init the Occurrence struct */
      SET_POS( wordStart - textToSearch, &word->first, 0,
               private->posBytes )
    }
  }

  /* Finished parsing text */
  return -1;
}

FindWordOccurrence
long FindWordOccurrence (
  char *wordToFind,
  long wordLength,
  long occurrenceToFind,
  char *textToSearch,
  long textLength,
  void *privateStorage,
  long storageSize
)
{
  Private *private = privateStorage;
  Word  *word;
  ulong hash;

  /* Make occurenceToFind zero-based */
  occurrenceToFind--;

  /* Generate hash value for word to find */
  hash = 0;
  {
    long remain = wordLength;
    uchar *p = (uchar *) wordToFind;
    while ( remain > 0 )
    {
      hash = (hash << 1) ^ private->hashCodes[*p++];
      remain--;
    }
    hash = (hash & 0xFFFFFF) | (wordLength << 24);
  }

  /* Look for word/occurrence in hash table */
  word = LookupWord( private, textToSearch, wordToFind,
                     wordLength, hash );
  if ( word )
  {
    Occurrence *occur = &word->first;
    long blockSize, pos, i;

    /* Word exists in hash table, so go down the occurrence list.  */
    switch ( private->posBytes )
    {
      case POS_2_BYTES: blockSize = 6;  break;
      case POS_3_BYTES: blockSize = 4;  break;
      case POS_4_BYTES: blockSize = 3;  break;
    }

    while ( occur && occurrenceToFind >= blockSize )
    {
      occurrenceToFind -= blockSize;
      occur = occur->next;
    }

    if ( occur )
    {
      GET_POS( pos, occur, occurrenceToFind,
               private->posBytes )
      if ( occurrenceToFind == 0 || pos != 0 )
        return pos;
      occurrenceToFind -= blockSize;
    }

    occur = word->last;
    for ( i = 0; i < blockSize; i++ )
    {
      GET_POS( pos, occur, i, private->posBytes )
      if ( pos == 0 )
        occurrenceToFind++;
    }
  }

  /* Not in parsed text, so check the unparsed text */
  if ( private->endParsedText != -1 )
  {
    char *p;
    if ( wordLength > 3 )
      p = BMH_Search(
              private->hashCodes,
              wordToFind,
              wordLength,
              occurrenceToFind,
              textToSearch + private->endParsedText,
              textToSearch + textLength,
              private->nullChar );
    else
      p = SimpleSearch(
              private->hashCodes,
              wordToFind,
              wordLength,
              occurrenceToFind,
              textToSearch + private->endParsedText,
              textToSearch + textLength );
    if (p)
      return (p - textToSearch);
  }

  /* Not found */
  return -1;
}

LookupWord 
/* Look up a word in the hash table */
static Word *LookupWord (
  Private *private,
  char    *textToSearch,
  char    *wordText,
  long    wordLength,
  ulong   hash
)
{
  Word *word = private->hashTable[ hash & HASH_MASK ];
  while ( word )
  {
    if ( word->hash == hash )
    {
      char *w1, *w2;
      long pos, remain = wordLength;

      /*
        The hash values match, so compare characters to make sure it’s the right word.  
        We already know the word length is correct since the length is contained
        in the upper eight bits of the hash value.
      */
      GET_POS( pos, &word->first, 0, private->posBytes )
      w1 = textToSearch + pos;
      w2 = wordText;
      while ( remain-- > 0 && *w1++ == *w2++ )
        ;
      if ( remain == -1 )
        return word;
    }
    word = word->next;
  }
  return NULL;
}

PickNullChar 
/*
  Find a character that doesn’t appear anywhere in the unparsed text.  BMH_Search() is 
  faster if such a character can be found.
*/
static char PickNullChar (
  Private *private,
  uchar   *textStart,
  uchar   *textEnd
)
{
  long i;
  uchar *p, occurs[ ALPHABET_SIZE ];

  for ( i = 0; i < ALPHABET_SIZE; i++ )
    occurs[i] = FALSE;

  for ( p = textStart; p < textEnd; p++ )
    occurs[*p] = TRUE;

  for ( i = 0; i < ALPHABET_SIZE; i++ )
    if ( occurs[i] == FALSE && private->hashCodes[i] == 0 )
      return i;

  return NO_NULL_CHAR;
}

BMH_Search
/*
  Search the unparsed text using the Boyer-Moore-Horspool algorithm.  Ideally a null 
  character is supplied (one that appears in neither the search string nor the text being 
  searched).  This allows the inner loop to be faster.
*/
static char *BMH_Search (
  ulong *hashCodes,       /* private->hashCodes     */
  char  *wordToFind,
  long  wordLength,
  long  occurrenceToFind, /* 0 is first occurrence  */
  char  *textStart,       /* start of unparsed text */
  char  *textEnd,         /* end of unparsed text   */
  char  nullChar          /* private->nullChar      */
)
{
  long  i;
  char  *text, *wordEnd;
  char  word[256];
  long  offset[ ALPHABET_SIZE ];

  /*
    Copy the search string to a private buffer, where
    the first character is the null character.
  */
  word[0] = nullChar;
  for ( i = 0; i < wordLength; i++ )
    word[i+1] = wordToFind[i];

  /* Set up the offset[] lookup table */
  for ( i = 0; i < ALPHABET_SIZE; i++ )
    offset[i] = wordLength;

  for ( i = 1; i < wordLength; i++ )
    offset[ word[i] ] = wordLength - i;

  /* Let the search begin... */
  wordEnd = word + wordLength;
  text = textStart + wordLength - 1;

  if ( nullChar == NO_NULL_CHAR )
  {
    /* No null character, so use a slower inner loop */
    while ( text < textEnd )
    {
      long i;
      char *p, *q;
      for ( i = wordLength, p = wordEnd, q = text;
            i > 0 && *p == *q;
            i--, p--, q-- )
        ;
/*If i == 0, we have found the search string.  Now we make sure that it is delimited.*/
      if ( i == 0 && hashCodes[*q] == 0 &&
           (text+1 == textEnd || hashCodes[text[1]] == 0) )
      {
        if ( occurrenceToFind == 0 )
          return q+1;
        occurrenceToFind--;
      }

      text += offset[*text];
    }
  }
  else
  {
    /* There is a null character (usual case), 
        so we can use a faster and simpler inner loop. */
    while ( text < textEnd )
    {
      char *p, *q;
      for ( p = wordEnd, q = text; *p == *q; p--, q-- )
        ;
      if ( p == word && hashCodes[*q] == 0 &&
           (text+1 == textEnd || hashCodes[text[1]] == 0) )
      {
        if ( occurrenceToFind == 0 )
          return q+1;
        occurrenceToFind--;
      }
      text += offset[*text];
    }
  }
  return NULL;
}

SimpleSearch
/*
  Search the unparsed text using a simple search algorithm.  Note that wordLength 
  must be 1, 2, or 3.  This algorithm runs faster than BMH_Search() for small search 
  strings.
*/
static char *SimpleSearch(
  ulong *hashCodes,       /* private->hashCodes      */
  char  *wordToFind,
  long  wordLength,       /* 1..3                    */
  long  occurrenceToFind, /* 0 is 1st occurrence     */
  char  *textStart,       /* start of unparsed text  */
  char  *textEnd          /* end of all text         */
)
{
  char *text, first;

  first = wordToFind[0];
  text = textStart;

  if ( wordLength == 1 )
  {
    while ( text < textEnd )
    {
      while ( text < textEnd && *text != first )
        text++;
      if ( hashCodes[*(text-1)] == 0 &&
           hashCodes[text[wordLength]] == 0 )
      {
        if ( occurrenceToFind == 0 )
          return text;
        occurrenceToFind--;
      }
    text++;
    }
  }
  else if ( wordLength == 2 )
  {
    while ( text < textEnd )
    {
      while ( text < textEnd && *text != first )
        text++;
      if ( text[1] == wordToFind[1] &&
           hashCodes[*(text-1)] == 0 &&
           hashCodes[text[wordLength]] == 0 )
      {
        if ( occurrenceToFind == 0 )
          return text;
        occurrenceToFind--;
      }
    text++;
    }
  }
  else /* wordLength == 3 */
  {
    while ( text < textEnd )
    {
      while ( text < textEnd && *text != first )
        text++;
      if ( text[1] == wordToFind[1] &&
           text[2] == wordToFind[2] &&
           hashCodes[*(text-1)] == 0 &&
           hashCodes[text[wordLength]] == 0 )
      {
        if ( occurrenceToFind == 0 )
          return text;
        occurrenceToFind--;
      }
    text++;
    }
  }
  return NULL;
}

 

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BusyContacts is a contact manager for OS X that makes creating, finding, and managing contacts faster and more efficient. It brings to contact management the same power, flexibility, and sharing... Read more
Capture One Pro 8.2.0.82 - RAW workflow...
Capture One Pro 8 is a professional RAW converter offering you ultimate image quality with accurate colors and incredible detail from more than 300 high-end cameras -- straight out of the box. It... Read more
Backblaze 4.0.0.872 - Online backup serv...
Backblaze is an online backup service designed from the ground-up for the Mac.With unlimited storage available for $5 per month, as well as a free 15-day trial, peace of mind is within reach with... Read more
Little Snitch 3.5.2 - Alerts you about o...
Little Snitch gives you control over your private outgoing data. Track background activity As soon as your computer connects to the Internet, applications often have permission to send any... Read more
Monolingual 1.6.4 - Remove unwanted OS X...
Monolingual is a program for removing unnecesary language resources from OS X, in order to reclaim several hundred megabytes of disk space. If you use your computer in only one (human) language, you... Read more
CleanApp 5.0 - Application deinstaller a...
CleanApp is an application deinstaller and archiver.... Your hard drive gets fuller day by day, but do you know why? CleanApp 5 provides you with insights how to reclaim disk space. There are... Read more
Fantastical 2.0 - Create calendar events...
Fantastical is the Mac calendar you'll actually enjoy using. Creating an event with Fantastical is quick, easy, and fun: Open Fantastical with a single click or keystroke Type in your event details... Read more
Cocktail 8.2 - General maintenance and o...
Cocktail is a general purpose utility for OS X that lets you clean, repair and optimize your Mac. It is a powerful digital toolset that helps hundreds of thousands of Mac users around the world get... Read more
Direct Mail 4.0.4 - Create and send grea...
Direct Mail is an easy-to-use, fully-featured email marketing app purpose-built for OS X. It lets you create and send great looking email campaigns. Start your newsletter by selecting from a gallery... Read more

Fast & Furious: Legacy's Creati...
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N-Fusion and 505's Ember is Totally...
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These are All the Apple Watch Apps and G...
The Apple Watch is less than a month from hitting store shelves, and once you get your hands on it you're probably going to want some apps and games to install. Fear not! We've compiled a list of all the Apple Watch apps and games we've been able to... | Read more »
Appy to Have Known You - Lee Hamlet Look...
Being at 148Apps these past 2 years has been an awesome experience that has taught me a great deal, and working with such a great team has been a privilege. Thank you to Rob Rich, and to both Rob LeFebvre and Jeff Scott before him, for helping me... | Read more »
Hands-On With Allstar Heroes - A Promisi...
Let’s get this out of the way quickly. Allstar Heroes looks a lot like a certain other recent action RPG release, but it turns out that while it’s not yet available here, Allstar Heroes has been around for much longer than that other title. Now that... | Read more »
Macho Man and Steve Austin Join the Rank...
WWE Immortals, by Warner Bros. Interactive Entertainment and WWE, has gotten a superstar update. You'll now have access to Macho Man Randy Savage and Steve Austin. Both characters have two different versions: Macho Man Randy Savage Renegade or Macho... | Read more »
Fearless Fantasy is Fantastic for the iF...
I actually had my first look at Fearless Fantasy last year at E3, but it was on a PC so there wasn't much for me to talk about. But now that I've been able to play with a pre-release version of the iOS build, there's quite a bit for me to talk... | Read more »
MLB Manager 2015 (Games)
MLB Manager 2015 5.0.14 Device: iOS Universal Category: Games Price: $4.99, Version: 5.0.14 (iTunes) Description: Guide your favorite MLB franchise to glory! MLB Manager 2015, officially licensed by MLB.com and based on the award-... | Read more »
Breath of Light (Games)
Breath of Light 1.0.1421 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.1421 (iTunes) Description: Hold a quiet moment. Breath of Light is a meditative and beautiful puzzle game with a hypnotic soundtrack by... | Read more »
WWE WrestleMania Tags into the App Store
Are You ready to rumble? The official WWE WrestleMania app, by World Wrestling Entertainment, is now available. Now you can get all your WrestleMania info in one place before anyone else. The app offers details on superstar signings, interactive... | Read more »

Price Scanner via MacPrices.net

13-inch 2.5GHz MacBook Pro (refurbished) avai...
The Apple Store has Apple Certified Refurbished 13″ 2.5GHz MacBook Pros available for $829, or $270 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free: - 13″ 2.... Read more
Save up to $80 on iPad Air 2s, NY tax only, f...
 B&H Photo has iPad Air 2s on sale for $80 off MSRP including free shipping plus NY sales tax only: - 16GB iPad Air 2 WiFi: $469.99 $30 off - 64GB iPad Air 2 WiFi: $549.99 $50 off - 128GB iPad... Read more
iMacs on sale for up to $205 off MSRP
B&H Photo has 21″ and 27″ iMacs on sale for up to $205 off MSRP including free shipping plus NY sales tax only: - 21″ 1.4GHz iMac: $1019 $80 off - 21″ 2.7GHz iMac: $1189 $110 off - 21″ 2.9GHz... Read more
Färbe Technik Offers iPhone Battery Charge LI...
Färbe Technik, which manufactures and markets of mobile accessories for Apple, Blackberry and Samsung mobile devices, is offering tips on how to keep your iPhone charged while in the field: •... Read more
Electronic Recyclers International CEO Urges...
Citing a recent story on CNBC about concerns some security professionals have about the forthcoming Apple Watch, John Shegerian, Chairman and CEO of Electronic Recyclers International (ERI), the... Read more
Save up to $380 with Apple refurbished iMacs
The Apple Store has Apple Certified Refurbished iMacs available for up to $380 off the cost of new models. Apple’s one-year warranty is standard, and shipping is free: - 27″ 3.5GHz 5K iMac – $2119 $... Read more
Mac minis on sale for up to $75 off, starting...
MacMall has Mac minis on sale for up to $75 off MSRP including free shipping. Their prices are the lowest available for these models from any reseller: - 1.4GHz Mac mini: $459.99 $40 off - 2.6GHz Mac... Read more
College Student Deals: Additional $50 off Mac...
Take an additional $50 off all MacBooks and iMacs at Best Buy Online with their College Students Deals Savings, valid through April 11, 2015. Anyone with a valid .EDU email address can take advantage... Read more
Mac Pros on sale for up to $260 off MSRP
B&H Photo has Mac Pros on sale for up to $260 off MSRP. Shipping is free, and B&H charges sales tax in NY only: - 3.7GHz 4-core Mac Pro: $2799, $200 off MSRP - 3.5GHz 6-core Mac Pro: $3719.99... Read more
13-inch 2.5GHz MacBook Pro on sale for $100 o...
B&H Photo has the 13″ 2.5GHz MacBook Pro on sale for $999 including free shipping plus NY sales tax only. Their price is $100 off MSRP. Read more

Jobs Board

DevOps Software Engineer - *Apple* Pay, iOS...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
*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
Sr. Technical Services Consultant, *Apple*...
**Job Summary** Apple Professional Services (APS) has an opening for a senior technical position that contributes to Apple 's efforts for strategic and transactional Read more
Lead *Apple* Solutions Consultant - Retail...
**Job Summary** Job Summary The Lead ASC is an Apple employee who serves as the Apple business manager and influencer in a hyper-business critical Reseller's store Read more
*Apple* Pay - Site Reliability Engineer - Ap...
**Job Summary** Imagine what you could do here. At Apple , great ideas have a way of becoming great products, services, and customer experiences very quickly. Bring Read more
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