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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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Apple iTunes lets you organize and play digital music and video on your computer. It can automatically download new music, app, and book purchases across all your devices and computers. And it's a... Read more
LibreOffice 4.4.3 - Free, open-source of...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
FoldersSynchronizer 4.2.1 - Synchronize...
FoldersSynchronizer is a popular and useful utility that synchronizes and backs-up files, folders, disks and boot disks. On each session you can apply special options like Timers, Multiple Folders,... Read more
Simon 4.0.2 - Monitor changes and crashe...
Simon monitors websites and alerts you of crashes and changes. Select pages to monitor, choose your alert options, and customize your settings. Simon does the rest. Keep a watchful eye on your... Read more
Cocktail 8.1.2 - General maintenance and...
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
Cyberduck 4.6.4 - FTP and SFTP browser....
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
Herald 5.0.2 - Notification plugin for M...
Note: Versions 2.1.3 (for OS X 10.7), 3.0.6 (for OS X 10.8), and 4.0.8 (for OS X 10.9) are no longer supported by the developer. Herald is a notification plugin for Mail.app, Apple's Mac OS X email... Read more
DEVONthink Pro 2.8.3 - Knowledge base, i...
Save 10% with our exclusive coupon code: MACUPDATE10 DEVONthink Pro is your essential assistant for today's world, where almost everything is digital. From shopping receipts to important research... Read more
Boom 2 1.0.1 - System-wide pro audio app...
Boom 2 is a system-wide volume booster and equalizer app that is designed especially for OS X 10.10 Yosemite. It comes with a smart interface, self-calibrates itself according to your Mac, offers... Read more

Playworld Superheroes Review
Playworld Superheroes Review By Tre Lawrence on January 30th, 2015 Our Rating: :: HERO CRAFTINGUniversal App - Designed for iPhone and iPad It’s all about the imagination, fighting bad creatures — and looking good while doing so.   | Read more »
Join the SpongeBob Bubble Party in this...
Join the SpongeBob Bubble Party in this New Match 3 Bubble Poppin’ Frenzy Posted by Jessica Fisher on January 30th, 2015 [ permalink ] | Read more »
Handpick Review
Handpick Review By Jennifer Allen on January 30th, 2015 Our Rating: :: TANTALIZING SUGGESTIONSiPhone App - Designed for the iPhone, compatible with the iPad Handpick will make you hungry, as well as inspire you to cook something... | Read more »
Storm the Halls of Echo Base in First St...
Storm the Halls of Echo Base in First Star Wars: Galactic Defense Event Posted by Jessica Fisher on January 30th, 2015 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Contradiction Review
Contradiction Review By Tre Lawrence on January 30th, 2015 Our Rating: :: SPOT THE LIEiPad Only App - Designed for the iPad Contradiction is a live action point and click adventure that’s pretty engaging.   Developer: Tim Follin... | Read more »
Unlock Sunshine Girl in Ironkill with th...
Unlock Sunshine Girl in Ironkill with this special 148Apps code Posted by Rob Rich on January 29th, 2015 [ permalink ] Robo-fighter Ironkill has been out on iOS a | Read more »
Crossroad Zombies Review
Crossroad Zombies Review By Jordan Minor on January 29th, 2015 Our Rating: :: CROSSWALKING DEADiPad Only App - Designed for the iPad Crossroad Zombies is a rough draft of a cool genre mash-up.   | Read more »
Blood Brothers 2 – Tips, Cheats, and Str...
War is hell: Is it the kind of hell you want to check out? Read our Blood Brothers 2 review to find out! Blood Brothers 2, DeNA’s follow-up to the original Blood Brothers, is an intriguing card collecting / role-playing / strategy hybrid. There’s... | Read more »
Blood Brothers 2 Review
Blood Brothers 2 Review By Nadia Oxford on January 29th, 2015 Our Rating: :: AN AGGRAVATING RELATIVEUniversal App - Designed for iPhone and iPad Blood Brothers 2 is built on a simple, solid foundation, but its free-to-play system... | Read more »
I AM BREAD, the Toast of the Town, is Ro...
Have you ever dreamt of being deliciously gluten-y? Do you feel passionate about Rye and Wheat? The guys at Bossa Studios do and that is why they are bringing I AM BREAD to iOS soon. The loafy app will feature all the new content that is being... | Read more »

Price Scanner via MacPrices.net

Intel Aims to Transform Workplace With 5th-Ge...
Intel Corporation today announced the availability of its 5th generation Intel Core vPro processor family that provides cutting-edge features to enable a new and rapidly shifting workplace. To meet... Read more
iOS App Sharalike Introduces New Instant Smar...
Sharalike slideshow and photo management software for iOS, is making it easier than ever to create shareable meaningful moments with its new instant SmartShow technology. Staying organized is a goal... Read more
Apple Becomes World’s Largest Smartphone Vend...
According to the latest research data from Strategy Analytics, as global smartphone shipments grew 31 percent annually to reach a record 380 million units in the fourth quarter of 2014. Apple became... Read more
Cut the Cord: OtterBox Resurgence Power Case...
Dead batteries and broken phones are two of the biggest issues for smartphone users today. Otterbox addresses both with the new Resurgence Power Case for Apple iPhone 6, promising to make those panic... Read more
13-inch Retina MacBook Pros on sale for up to...
B&H Photo has 13″ Retina MacBook Pros on sale for $200 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 2.6GHz/128GB Retina MacBook Pro: $1199.99 save $100 - 13″ 2.6GHz/... Read more
15-inch 2.5GHz Retina MacBook Pro on sale for...
 B&H Photo has the 15″ 2.5GHz Retina MacBook Pro on sale for $2319.99 including free shipping plus NY sales tax only. Their price is $180 off MSRP, and it’s the lowest price available for this... Read more
Back in stock: Refurbished iPod nanos for $99...
The Apple Store has Apple Certified Refurbished 16GB iPod nanos available for $99 including free shipping and Apple’s standard one-year warranty. That’s $50 off the cost of new nanos. Most colors are... Read more
Apple lowers price on refurbished 256GB MacBo...
The Apple Store has lowered prices on Apple Certified Refurbished 2014 MacBook Airs with 256GB SSDs, now available for up to $200 off the cost of new models. An Apple one-year warranty is included... Read more
New Good Management Suite Simplifies Enterpri...
Good Technology has announced the availability of the Good Management Suite, a comprehensive cross-platform solution for organizations getting started with mobile business initiatives. Built on the... Read more
15-inch 2.0GHz Retina MacBook Pro (refurbishe...
The Apple Store has Apple Certified Refurbished previous-generation 15″ 2.0GHz Retina MacBook Pros available for $1489 including free shipping plus Apple’s standard one-year warranty. Their price is... Read more

Jobs Board

*Apple* Solutions Consultant- Retail Sales (...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Event Director, *Apple* Retail Marketing -...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global engagement strategy and team. Delivering an overarching brand Read more
At-Home Chat Specialist- *Apple* Online Stor...
**Job Summary** At Apple , we believe in hard work, a fun environment, and the kind of creativity and innovation that only comes about when talented people from diverse Read more
SW QA Engineer - *Apple* TV - Apple (United...
**Job Summary** The Apple TV team is looking for experienced Quality Assurance Engineers with a passion for delivering first in class home entertainment solutions. **Key Read more
*Apple* Retail - Multiple Positions(US) - Ap...
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
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