TweetFollow Us on Twitter

Feb 98 Challenge

Volume Number: 14 (1998)
Issue Number: 2
Column Tag: Programmer's Challenge

Programmer's Challenge

by Bob Boonstra, Westford, MA

Image Decoder

This month's Challenge is much easier to state than it will be to implement. Your task this month is to write a decoder for Graphics Interchange Format images. GIF is a data stream-oriented file format used to define the transmission protocol of LZW-encoded bitmap data. Your code will read a file containing a GIF and draw the image in an offscreen graphics world. There are two versions of the GIF specification; this Challenge includes only the earlier and more common GIF87a format, not the GIF89a format. The format description is too long to include here, but you can find the GIF87a specification at: ftp://ftp.ncsa.uiuc.edu/misc/file.formats/graphics.formats/gif87a.doc

Other useful information on graphics formats in general is available at: http://www.cis.ohio-state.edu/hypertext/faq/usenet/graphics/fileformats-faq/top.html

The prototype for the code you should write is:

#include <QDOffscreen.h>
#include <stdio.h>
GWorldPtr ReadImage(FILE *inputFile);

The inputFile will have been opened for you in binary mode by the calling routine. ReadImage should read and parse the image, create a GWorld with the appropriate color table, draw the image in the GWorld, and return a GWorld pointer to the calling routine. The solution that correctly decodes a variety of images in the least amount of execution time will be the winner.

I thought for some time about the Compuserve / Unisys / LZW patent controverty before selecting this topic for the Challenge. The LZW algorithm used in GIF compression is patented by Unisys, and Unisys requires that any commercial software product that uses this algorithm, including software that reads GIF images, requires a license from Unisys. Freely distributed software does not require a license. Since the Challenge doesn't result in a software product, much less a commercial product, I decided to go ahead with this exploration of decoding efficiency.

This will be a native PowerPC Challenge, using the latest CodeWarrior environment. Solutions must be coded in C, C++, or Pascal. This Challenge was suggested by Peter Lewis, who earns 2 Challenge points for the suggestion.

Three Months Ago Winner

Congratulations to Jeff Mallett (Boulder Creek, CA) for submitting the winning entry to the Pente(tm) Challenge. The objective was to accumulate, in minimum execution time, the most points in a round-robin tournament of the board game Pente(tm). With only three entries, the tournament required only six games for each player to compete against each other player twice, once playing first and once playing second. Both the winning entry and the third-place entry by Randy Boring employed an alpha-beta search technique to find the best move, and both entries were successful in winning most of their games. Jeff's entry, however, was more efficient about pruning the search tree and therefore required significantly less execution time than Randy's entry. Since a point was deducted for each second of execution time, the winning entry lost significantly fewer points for inefficiency. In addition, the scoring algorithm in Jeff's AddStone routine takes advantage of all three methods of scoring points: captures, winning by placing 5 stones in a row, and leaving sequences of 4-in-a-row on the board at the conclusion of a game. His solution earned more points as a result, even though it won the same number of games as Randy's.

The table below lists the number of tournament wins, points earned, cumulative score, code size, data size, and programming language for each entry. The number in parentheses after the entrant's name is the total number of Challenge points earned in all Challenges to date prior to this one.

Name               Wins   Points   Score  Code  Data  Language
Jeff Mallett (74)    3      33     32.03  4872  7923    C
Sebastian Maurer     0      10      9.97  4860  208     C++
Randy Boring (66)    3      23   -374.90  7672  2649    C

Top 20 Contestants

Here are the Top Contestants for the Programmer's Challenge. The numbers below include points awarded over the 24 most recent contests, including points earned by this month's entrants. The scores have been adjusted to correct an error made in assigning points for the Stratego Challenge printed in the November issue.

Rank Name               Points
 1.  Munter, Ernst        200  
 2.  Boring, Randy         73
 3.  Cooper, Greg          61
 4.  Lewis, Peter          59
 5.  Mallett, Jeff         50
 6.  Nicolle, Ludovic      48
 7.  Murphy, ACC           34
 8.  Gregg, Xan            33
 9.  Antoniewicz, Andy     24
10.  Day, Mark             20
11.  Higgins, Charles      20
12.  Larsson, Gustav       20
13.  Studer, Thomas        20
14.  Gundrum, Eric         15
15.  Hart, Alan            14
16.  O'Connor, Turlough    14
17.  Picao, Miguel Cruz    14
18.  Saxton, Tom           12
19.  Cutts, Kevin          11
20.  8-way tie             10

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
2nd place            10 points
3rd place             7 points
4th place             4 points
5th place             2 points
finding bug           2 points
suggesting Challenge  2 points

Here is Jeff's winning solution:

MyPente.c
Copyright © 1997 Jeff Mallett
//
// Do a depth=1 search to sort moves. Then do a higher
// depth alpha-beta search to select the best move.
//
// Plays for score rather than to win. For example,
// doesn't try to win by getting 5 captures since
// there is no score incentive for this. It could be
// retuned to play for a win instead.

#include "Pente.h"

#define SEARCH_DEPTH 4
enum {
 _FRIEND = 0x0001,
 _ENEMY = 0x0002,
 _EMPTY = 0x0004,
 _WALL  = 0x0008
};

#define BORDER    1
#define BORDERS    2
#define INFINITY   32600
#define NA      0
#define MAX_CELLS   (31 + BORDERS) * (31 + BORDERS)

#define ESTIMATE_PLUS 1
#define WIN      2000
#define CAPTURE_SCORE 240
#define VULNERABLE   150

static short CHAIN_SCORE2[3][3] = {  //[color][open]
 { NA, NA, NA },
 { -1, -9, -2 },      // FRIEND
 { 1, 9, 2 }      // ENEMY
};
static short CHAIN_SCORE3[3][3] = {  //[color][open]
 { NA, NA, NA },
 { 3, 16, 40 },      // FRIEND
 { -2,-10,-30 }      // ENEMY
};
static short CHAIN_SCORE4[3][3] = {  //[color][open]
 {  NA, NA, NA },
 { 230, 240, 250 },  // FRIEND
 { -150,-155,-160 }  // ENEMY
};
static short CHAIN_SCORE5[3] = {    //[color]
 NA, WIN, -WIN
};
//                 1  2  3  4
static short BLOCK_SCORE[5] = { NA, 0, 14, 14, 22};
static short THREATS[] = {
 NA, NA,
 25, // 2: tria
 30, // 3: half-open four
 350, // 4: double trias
 370, // 5: tria + half-open four
 450, // 6: tessera or 2 half-open fours
 500, 500, 500, 500, 500, 500, 500, 500, 500, 500
};

static short gPreScore[MAX_CELLS], gEstimates[MAX_CELLS];
static short *gEstimatesStart, *gEstimatesEnd;
static short gBoard[MAX_CELLS], *gBoardStart, *gBoardEnd;
static short *gFirstStone, *gLastStone;
static short *gKillers[SEARCH_DEPTH], gPreviousThreats;
static short gDirections[8], *gDirectionsEnd;
static short gMoveNum, gScore, gStartDepth;
static short gBoardHalfSize, gSideLength, gBoardMax;
static short gCumCapturesFriend, gCumCapturesEnemy;
static short gAdjustment, gSE;

#define ADJUST(a)    ( (a) + gAdjustment )
#define TRANSLATE(x, y) \
 (gSideLength * ADJUST(y) + ADJUST(x))
#define GET_INDEX(p) ((p) - gBoard)
#define GET_X(i)   ( ((i) % gSideLength) - gAdjustment )
#define GET_Y(i)   ( ((i) / gSideLength) - gAdjustment )
#define UPDATE_ENDPOINTS(pSq, a, b) \
 if (pSq < a) a = pSq; \
 if (pSq > b) b = pSq

#define OPPONENT(side) (3 - (side))
#define OCCUPIED(x)   ((x) & (_FRIEND | _ENEMY))
#define EMPTY(x)    ((x) == _EMPTY)

// gChanges -- Array of unsigned longs containing data to
// undo moves
//   list of:
//     <pointer to position> <old position value>
//   terminated by a OL
static unsigned long gChanges[256], *gChangesEnd;
#define PUSH(x)    *(gChangesEnd++) = (x)
#define START_SAVE  PUSH(0L)
#define PUSH_SQ(pSq) \
  { PUSH((long)*(pSq)); PUSH((unsigned long)(pSq)); }
#define POP      *(--gChangesEnd)
#define TOP      *gChangesEnd

static short * ChooseNextMove();
static short AddStone(short alpha, short beta, short *pSq,
        short color, short depth,
        short capturesFriend, short capturesEnemy,
        short *firstStone, short *lastStone);
static long MyFindCaptures(Capture capture[], short *pSq,
        short us, short them);
static Boolean MyFindFive(short *pSq, short color);

InitPente
void InitPente(
 long boardHalfSize  /* e.g., 9 for a 19x19 board */
       /* all coordinates between -boardHalfSize
        and +boardHalfSize */
) {
 short i, j, *pSq;
 
 gBoardHalfSize = boardHalfSize;
 gSideLength = boardHalfSize * 2 + 1 + BORDERS;
 gSE = gSideLength + 1;
 gDirections[0] = -gSE;                // NW
 gDirections[1] = -gSideLength;        // N
 gDirections[2] = -gSideLength + 1;     // NE
 gDirections[3] = -1;                // W
 gDirections[4] = gSE;                // SE
 gDirections[5] = gSideLength;        // S
 gDirections[6] = gSideLength - 1;      // SW
 gDirections[7] = 1;                  // E
 gDirectionsEnd = &gDirections[8];
 
 gBoardMax = gSideLength * gSideLength;
 i = (gSideLength + 1) * BORDER;
 gBoardStart = &gBoard[i];
 gBoardEnd = &gBoard[gBoardMax - i];
 gEstimatesStart = &gEstimates[i];
 gEstimatesEnd = &gEstimates[gBoardMax - i];
 gFirstStone = gBoardEnd;
 gLastStone = gBoardStart;
 
 pSq = gBoard;
 do {
  *pSq = _WALL;
 } while (++pSq != gBoardStart);
 do {
  *pSq = _EMPTY;
 } while (++pSq != gBoardEnd);
 do {
  *pSq = _WALL;
 } while (++pSq < &gBoard[gBoardMax]);
 for (i = BORDER + boardHalfSize * 2 + 1;
    i<gBoardMax-gSideLength; i += gSideLength)
  for (j=0; j<BORDERS; ++j)
   gBoard[i+j] = _WALL;
 gCumCapturesFriend = gCumCapturesEnemy = gMoveNum = 0;
 gAdjustment = gBoardHalfSize + BORDER;
 gStartDepth = SEARCH_DEPTH - 1;
}

Pente
void Pente(
 Point opponentsMove,      /* your opponent moved here */
 Boolean playingFirst,      /* ignore opponentMove */
 Point *yourMove,          /* return your move here */
 Capture claimCaptures[],    /* return captured pairs here */
 long *numCaptures,       /* return # of claimCaptures */
 Boolean *claimVictory     /* return true if you claim
               victory with this move */
) {
 Point move;
 Capture opponentCaptures[8];
 
 short *pSq, *pNewSq, *d;
 short score, bestScore, i;
 short *pBestMove;
 
 *numCaptures = 0;
 *claimVictory = false;
 if (playingFirst) { // *** MOVE 1
  move.h = move.v = 0;
  pSq = &gBoard[TRANSLATE(0, 0)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 1;
  return;
 }
 
 i = TRANSLATE(opponentsMove.h, opponentsMove.v);
 pSq = &gBoard[i];
 *pSq = _ENEMY;
 UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
 ++gMoveNum;

 if (gMoveNum == 1) { // *** MOVE 2
  move.h = move.v = -2;
  pSq = &gBoard[TRANSLATE(-2, -2)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 2;
  return;
 }
 
 if (gMoveNum == 2) { // *** MOVE 3
  if (opponentsMove.v < opponentsMove.h) {
   if (opponentsMove.v < -opponentsMove.h) {
    // top triangle
    move.h = 0;
    move.v = 4;
   } else {
    // right triangle
    move.h = -4;
    move.v = 0;
   }
  } else {
   if (opponentsMove.v >= -opponentsMove.h) {
    // bottom triangle
    move.h = 0;
    move.v = -4;
   } else {
    // left triangle
    move.h = 4;
    move.v = 0;
   }
  }
  pSq = &gBoard[TRANSLATE(move.h, move.v)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 3;
  return;
 }

 gChangesEnd = gChanges;
 gCumCapturesEnemy +=
   MyFindCaptures(opponentCaptures, &gBoard[i],
           _ENEMY, _FRIEND);
 for (pSq = gEstimatesStart; pSq != gEstimatesEnd; ++pSq)
  *pSq = 0;
 for (pSq = gFirstStone; pSq <= gLastStone; ++pSq)
  if (OCCUPIED(*pSq)) {
   d = gDirections;
   do {
    pNewSq = pSq + *d;
    if (EMPTY(*pNewSq)) {
     gEstimates[GET_INDEX(pNewSq)] += ESTIMATE_PLUS;
     pNewSq += *d;
     if (EMPTY(*pNewSq)) {
      gEstimates[GET_INDEX(pNewSq)] += ESTIMATE_PLUS;
     }
    }
   } while (++d != gDirectionsEnd);
  }

 for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq)
  if (gEstimates[GET_INDEX(pSq)]) {
   i = GET_INDEX(pSq);
   gScore = gEstimates[i];
   gPreScore[i] = AddStone(-INFINITY, INFINITY, pSq,
            _FRIEND, 0, gCumCapturesFriend,
            gCumCapturesEnemy, gFirstStone,
            gLastStone);
  }

 for (i=0; i<SEARCH_DEPTH; ++i)
  gKillers[i] = NULL;
 bestScore = -INFINITY;
 pBestMove = NULL;
 pSq = ChooseNextMove();
 while (pSq) {
  i = GET_INDEX(pSq);
  gScore = gEstimates[i];
  score = AddStone(-INFINITY, -bestScore, pSq, _FRIEND,
       gStartDepth, gCumCapturesFriend,
       gCumCapturesEnemy, gFirstStone, gLastStone);
  gEstimates[i] = -1; // searched
  if (score > bestScore) {
   bestScore = score;
   pBestMove = pSq;
  }
  pSq = ChooseNextMove();
 }
  
 if (bestScore == -INFINITY) {
  for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq)
   if (EMPTY(*pSq) && !gEstimates[GET_INDEX(pSq)]) {
    gScore = 0;
    score = AddStone(-INFINITY, -bestScore, pSq, _FRIEND,
                  gStartDepth, gCumCapturesFriend,
                  gCumCapturesEnemy, gFirstStone, gLastStone);
    if (score > bestScore) {
     bestScore = score;
     pBestMove = pSq;
    }
   }
  if (bestScore == -INFINITY) {
   DebugStr("\p no move found - Pente");
   return; //no move
  }
 }
 
 *pBestMove = _FRIEND;
 UPDATE_ENDPOINTS(pBestMove, gFirstStone, gLastStone);
 i = GET_INDEX(pBestMove);
 move.h = GET_X(i);
 move.v = GET_Y(i);
 *yourMove = move;
 ++gMoveNum;
 // find captures
 *numCaptures = MyFindCaptures(claimCaptures, pBestMove,
          _FRIEND, _ENEMY);
 gCumCapturesFriend += *numCaptures;
 if (gCumCapturesFriend >= 5) {
  *claimVictory = true;
 } else {
  *claimVictory = MyFindFive(pBestMove, _FRIEND);
 }
}

TermPente
void TermPente(void) { }

ChooseNextMove
short * ChooseNextMove()
{
 short i, *pSq;
 short *found = NULL;
 short high = -INFINITY;
 for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq) {
  i = GET_INDEX(pSq);
  if (gEstimates[i] > 0 && gPreScore[i] > high) {
   found = pSq;
   high = gPreScore[i];
  }
 }
 return found;
}

AddStone
// Alpha-beta search routine
// returns score of how good it is for color
// alpha and beta apply for the opponent after the move
// is made
// gScore is absolute: + for _FRIEND
short AddStone(short alpha, short beta, short *pSq,
    short color, short depth, short capturesFriend,
    short capturesEnemy, short *firstStone,
    short *lastStone)
{
 register short *pNewSq, *d;
 short x, bestScore, t, *pEnd;
 short open, *killer;
 short threats, blocks, vulnerable;
 short opponent = OPPONENT(color);
 short saveScore = gScore;
  
 START_SAVE;
 threats = blocks = vulnerable = 0;
 d = gDirections;
 do {
  pNewSq = pSq + *d;
  
  if (*pNewSq == color) { // Next to friend
   if (d <= &gDirections[3]) {
    x = 1;
    open = 0;
    for (pNewSq += *d; *pNewSq == color; pNewSq += *d)
     ++x;
    if (EMPTY(*pNewSq))
     open = 1;
    for (pNewSq = pSq + *(d+4); *pNewSq == color;
       pNewSq += *(d+4))
     ++x;
    if (EMPTY(*pNewSq))
     ++open;
   } else {
    t = *(pSq + *(d-4));
    if (t == color)
     continue;
    x = 1;
    open = 0;
    if (EMPTY(t))
     open = 1;
    for (pNewSq += *d; *pNewSq == color; pNewSq += *d)
     ++x;
    if (EMPTY(*pNewSq))
     ++open;
   }
   
   switch (x) {
    case 1:  // 2-in-a-row
     gScore += CHAIN_SCORE2[color][open];
     if (open == 1)
      ++vulnerable;
     break;
    case 2:  // 3-in-a-row
     gScore += CHAIN_SCORE3[color][open];
     if (open == 2)
      threats += 2;        // tria = 2
     break;
    case 3:  // 4-in-a-row
     gScore += CHAIN_SCORE4[color][open];
     threats += open * 3;  // tessera = 6, half-open = 3
     break;
    default:  // 5-in-a-row (or more)
     gScore += CHAIN_SCORE5[color];
     threats = -99;        // game over
     break;
   }
   
  } else if (*pNewSq == opponent) {  // Next to enemy
   x = 1;
   for (pNewSq += *d; *pNewSq == opponent; pNewSq += *d)
    ++x;
    
   if (EMPTY(*pNewSq)) {
    blocks += BLOCK_SCORE[x];
   } else if (x == 2 && *pNewSq == color) {
    t = CAPTURE_SCORE;
    if (color != _FRIEND)
     t = -t;
    gScore += t;
    if (color == _FRIEND) {
     if (++capturesFriend >= 5) {
      threats = -99;  // game over
     }
    } else {  // color == _ENEMY
     if (++capturesEnemy >= 5) {
      threats = -99;  // game over
     }
    }
    if (depth) {
     pNewSq = pSq + *d;
     PUSH_SQ(pNewSq);
     *pNewSq = _EMPTY;
     pNewSq += *d;
     PUSH_SQ(pNewSq);
     *pNewSq = _EMPTY;
    }
   }
  }
 } while (++d != gDirectionsEnd);
  
 if (threats < 0) {
  // Game over
  bestScore = gScore;
  if (color != _FRIEND)
   bestScore = -bestScore;
  goto RESTORE;
 }
   
  // Not forced to make a bad move
 if (color == _FRIEND) {
  if (gScore < saveScore)
   gScore = saveScore;
 } else if (gScore > saveScore)
  gScore = saveScore;
 if (depth) {
  // Add stone
  PUSH_SQ(pSq);
  *pSq = color;
  UPDATE_ENDPOINTS(pSq, firstStone, lastStone);
  --depth; 
  gPreviousThreats = threats;
  bestScore = -INFINITY;
  // Killer move?
  killer = gKillers[depth];
  if (killer && EMPTY(*killer)) {
   saveScore = gScore;
    bestScore = AddStone(-beta, -alpha, killer,
           opponent, depth, capturesFriend,
           capturesEnemy, firstStone, lastStone);
   gScore = saveScore;
   if (bestScore > alpha) {
    if (bestScore >= beta) {
     bestScore = -bestScore;
     goto RESTORE;
    }
    alpha = bestScore;
   }
  }
  
  pEnd = lastStone + gSE;
  if (pEnd >= gBoardEnd)
   pEnd = gBoardEnd - 1;
  pSq = firstStone - gSE;
  if (pSq < gBoardStart)
   pSq = gBoardStart;
  do {
   if (EMPTY(*pSq) && pSq != killer) {
    d = gDirections;
    do {
     pNewSq = pSq + *d;
     if (OCCUPIED(*pNewSq) &&
        (*(pNewSq + *d) == *pNewSq ||
         *(pSq  - *d) == *pNewSq))
      break;
    } while (++d != gDirectionsEnd);
    if (d != gDirectionsEnd) {
     saveScore = gScore;
      t = AddStone(-beta, -alpha, pSq, opponent,
         depth, capturesFriend, capturesEnemy,
         firstStone, lastStone);
     gScore = saveScore;
     if (t > bestScore) {
      bestScore = t;
      if (t > alpha) {
       if (t >= beta) {
        gKillers[depth] = pSq;
        break;
       }
       if (depth >= gStartDepth-1)
        gKillers[depth] = pSq;
       alpha = t;
      }
     }
    }
   }
  } while (++pSq <= pEnd);
  if (bestScore == -INFINITY) {
   ++depth;
   goto TERMINAL;
  }
  bestScore = -bestScore;
  
 } else { // !depth
TERMINAL:
  bestScore = gScore;
  if (color != _FRIEND)
   bestScore = -bestScore;

  // Winning threats
  if (gPreviousThreats >= 5) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats >= 5) {
   bestScore += THREATS[threats];
  } else if (gPreviousThreats == 4) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats == 4) {
   bestScore += THREATS[threats];
  } else if (gPreviousThreats) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats) {
   bestScore += THREATS[threats];
  }
  bestScore += blocks - vulnerable * VULNERABLE;
 }
 
RESTORE: 
 while (POP) {
  pSq = (short *)TOP;
  *pSq = POP;
 }
  
 return bestScore;
}

MyFindCaptures
long MyFindCaptures(Capture capture[], short *pSq,
          short us, short them)
{
 short i, *p1, *p2;
 short myCaptures = 0;
 short *d = gDirections;
 
 do {
  p1 = pSq + *d;
  if (*p1 == them) {
   p2 = p1 + *d;
   if (*p2 == them && *(p2 + *d) == us) {
    *p1 = *p2 = _EMPTY;
    i = GET_INDEX(p1);
    capture[myCaptures].stone1.h = GET_X(i);
    capture[myCaptures].stone1.v = GET_Y(i);
    i = GET_INDEX(p2);
    capture[myCaptures].stone2.h = GET_X(i);
    capture[myCaptures].stone2.v = GET_Y(i);
    ++myCaptures;
   }
  }
 } while (++d != gDirectionsEnd);
 return myCaptures;
}

MyFindFive
Boolean MyFindFive(short *pSq, short color)
{
 short x, *d, *pNewSq, i;
 
 d = gDirections;
 i = 0;
 do {
  x = 1;
  for (pNewSq = pSq + *d; *pNewSq == color; pNewSq += *d)
   ++x;
  for (pNewSq = pSq + *(d+4); *pNewSq == color;
     pNewSq += *(d+4))
   ++x;
  if (x >= 5)
   return true;
  ++d;
 } while (++i < 4);
 return false;
}
 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Shadow Blade: Reload guide - How to hack...
Shadow Blade: Reload is the kind of action-platformer that would have happily sucked up hours of your time on a console a few years back.Now, you can take it with you wherever you go, and its mobile conversion is not too shabby at all. To help you... | Read more »
Tomb of the Mask guide - How to increase...
Tomb of the Mask is a great endless arcade game from Happymagenta in which quick reflexes and a persistent attitude can go a long way toward earning a top score. Check out these tips to see if you can give yourself an edge on the leaderboards. [... | Read more »
Smooth Operator! (Games)
Smooth Operator! 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: Smooth Operator is a weird, weird two-player kissing game. Squeeze in for 2 player fun on a single iPad, creating awkward... | Read more »
Sinless: Remastered (Games)
Sinless: Remastered 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: | Read more »
_PRISM Guide - How to solve those puzzle...
_PRISM is a rather delightful puzzle game that’s been tailor made for touch screens. While part of the fun is figuring things out as you go along, we thought we’d offer you a helping hand at getting in the right mindset. Don’t worry about messing... | Read more »
Fractal Space (Games)
Fractal Space 1.3.1 Device: iOS Universal Category: Games Price: $.99, Version: 1.3.1 (iTunes) Description: Live the memorable experience of Fractal Space, a unique first person adventure & puzzle game by Haze Games! Will you... | Read more »
Set off on an adventure through the Cand...
Like match three puzzlers? If so, Jelly Blast, the innovative iOS and Android game which launched last year, is worth a look. Jelly Blast sees you head off on an epic adventure through the Candy Kingdom with your friends Lily, Mr. Hare, and Mr.... | Read more »
Ellipsis - Touch. Explore. Survive. (...
Ellipsis - Touch. Explore. Survive. 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: | Read more »
Abzorb (Games)
Abzorb 1 Device: iOS Universal Category: Games Price: $2.99, Version: 1 (iTunes) Description: Abzorb is a tilt game about consuming orbs by getting as close as you can to them without touching. By tilting your mobile device, collect... | Read more »
A Short Tale (Games)
A Short Tale 1.0 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0 (iTunes) Description: It’s been years since I lost Ben, so long yet it doesn’t seem long enough. I never thought I’d return here, to where everything... | Read more »

Price Scanner via MacPrices.net

cb Hardcase – Handmade and Premium Protective...
Baden-Baden, Germany based company cb innovations has introduced the new cb Hardcase for iPhone. Featuring fine Italian Premium leather that makes for a unique look and feel, the cb Hardcase... Read more
Sale! B&H Photo offers 12-inch Retina Mac...
B&H Photo has 12″ Retina MacBooks on sale for $300 off MSRP for a limited time. Shipping is free, and B&H charges NY tax only: - 12″ 1.1GHz Gray Retina MacBook: $999 $300 off MSRP - 12″ 1.... Read more
App Annie Reveals Future of the App Economy:...
App Annie, a San Francisco based mobile app data and insights platform, has launched its first comprehensive app economy forecast. This new offering will provide brands, agencies, investors and app... Read more
Apple restocks Certified Refurbished Mac mini...
Apple has restocked Certified Refurbished 2014 Mac minis, with models available starting at $419. Apple’s one-year warranty is included with each mini, and shipping is free: - 1.4GHz Mac mini: $419 $... Read more
What iPad Pro Still Needs To Make It Truly Pr...
I love my iPad Air 2. So much that I’m grudgingly willing to put up with its compromises and limitations as a production tool in order to take advantage of its virtues. However, since a computer for... Read more
21-inch 3.1GHz 4K on sale for $1399, $100 off...
B&H Photo has the 21″ 3.1GHz 4K iMac on sale $1399 for a limited time. Shipping is free, and B&H charges NY sales tax only. Their price is $100 off MSRP: - 21″ 3.1GHz 4K iMac (MK452LL/A): $... Read more
Apple price trackers, updated continuously
Scan our Apple Price Trackers for the latest information on sales, bundles, and availability on systems from Apple’s authorized internet/catalog resellers. We update the trackers continuously: - 15″... Read more
Save up to $240 with Apple Certified Refurbis...
Apple is now offering Certified Refurbished 12″ Retina MacBooks for up to $240 off the cost of new models. Apple will include a standard one-year warranty with each MacBook, and shipping is free. The... Read more
Apple refurbished 13-inch Retina MacBook Pros...
Apple has Certified Refurbished 13″ Retina MacBook Pros available for up to $270 off the cost of new models. An Apple one-year warranty is included with each model, and shipping is free: - 13″ 2.7GHz... Read more
Apple refurbished Time Capsules available for...
Apple has certified refurbished Time Capsules available for $120 off MSRP. Apple’s one-year warranty is included with each Time Capsule, and shipping is free: - 2TB Time Capsule: $179, $120 off - 3TB... Read more

Jobs Board

Lead Engineer *Apple* OSX & Hardware -...
Lead Engineer Apple OSX & Hardware **Job ID:** 3125919 **Full/Part\-Time:** Full\-time **Regular/Temporary:** Regular **Listed:** 2016\-02\-10 **Location:** Cary, Read more
*Apple* Mobile Master - Best Buy (United Sta...
Job Title Apple Mobile Master **Brand** Best Buy **Job Description** **What does a Best Buy Apple Mobile Master do?** At Best Buy, our mission is to leverage the Read more
Infrastructure Engineer - *Apple* /Mac - Rem...
…part of a team Requires proven problem solving skills Preferred Additional: Apple Certified System Administrator (ACSA) Apple Certified Technical Coordinator (ACTC) Read more
Lead Engineer - *Apple* OSX & Hardware...
Lead Engineer - Apple OSX & Hardware **Job ID:** 3125919 **Full/Part\-Time:** Full\-time **Regular/Temporary:** Regular **Listed:** 2016\-02\-10 **Location:** Cary, Read more
Simply Mac *Apple* Specialist- Service Repa...
Simply Mac is the largest premier retailer of Apple products in the nation. In order to support our growing customer base, we are currently looking for a driven Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.