Jul 98 Prog Challenge

Volume Number: 14 (1998)
Issue Number: 7
Column Tag: Programmer's Challenge

# Jul 97 Programmer's Challenge

by Bob Boonstra, Westford, MA

### Going Up?

Welcome to the Programmer's Challenge Skyscraper. Your Challenge this month is to assume control of our skyscraper's elevators and efficiently move a dedicated crew of simulated employees up and down the building.

The prototype for the code you should write is:

```#if defined(__cplusplus)
extern "C" {
#endif

#define kMaxFloors 500
#define kMaxElevators 100
#define kElevatorCapacity 16

typedef enum {         /* commanded action for elevator car */
kGoingUp=1,          /* send car up one floor */
kGoingDown,          /* send car down one floor */
kStoppedGoingUp,     /* stop car at an intermediate floor, car going up */
kStoppedGoingDown,   /* stop car at an intermediate floor, car going down */
kStoppedIdle         /* stop car, car in idle state */
} CarAction;

typedef struct CarState {
long atFloor;        /* current location of car */
long goingToFloor[kMaxFloors];
/* goingToFloor[i] is the number of passengers in the car is going to floor [i] */
} CarState;

/* return value of TRUE means Elevator should exit */
CarAction action[kMaxElevators],  /* direction you move each elevator */
CarState newState[kMaxElevators],  /* returns new state of each elevator */
Boolean stopsAtFloor[kMaxFloors],
/* stopsAtFloor[i]==TRUE means elevator stops at floor i */
Boolean callGoingUp[kMaxFloors],
/* callGoingUp[i]==TRUE means a passenger on floor i wants to go up */
Boolean callGoingDown[kMaxFloors]
/* callGoingDown[i]==TRUE means a passenger on floor i wants to go down */
);

void Elevator(
long numFloors,     /* number of floors in our building, < kMaxFloors */
long numElevators,  /* number of elevators in our building, <
kMaxElevators */
);
#if defined(__cplusplus)
}
#endif
```

Your Elevator routine will be called with the number of floors (numFloors) in our simulated skyscraper, the number of elevators (numElevators) at your command, and a callback routine (AdvanceTime). You should repeatedly call AdvanceTime, commanding an action and a set of constraints (stopsAtFloor) for each elevator car and receiving back the newState of each car. AdvanceTime will also provide an indicator of whether any prospective passengers on floor i have called an elevator to take them higher (callGoingUp[i]) or lower (callGoingDown[i]).

The newState returned by AdvanceTime provides the location of each car and the number of occupants. atFloor is the floor at which the car is now located. Our elevator passengers are extraordinarily cooperative -- on entering, they all indicate their destination by pressing the button corresponding to their floor, whether or not that floor has already been selected, allowing AdvanceTime to give you an accurate count of the passengers going to floor i (goingToFloor[i]). Our passengers are also extraordinarily swift --Êthey exit and enter in such an orderly fashion that the passenger exchange takes place in one time step.

Each call to AdvanceTime will move all the elevators one floor in the direction you indicate. If you stop the car by setting action to kStoppedGoingUp, kStoppedGoingDown, or kStoppedIdle, passengers headed for the current floor will exit and new passengers, up to kElevatorCapacity, will enter. Almost always, passengers headed to higher (or lower) floors will only enter elevators that are kStoppedGoingUp (kStoppedGoingDown) or kStoppedIdle, but occasionally someone will be confused and enter an elevator headed in the wrong direction.

You are free to run your elevators anyway you see fit, except that a car declared to be kGoingUp (or kGoingDown) needs to continue going up (or down) until all passengers headed in that direction have exited. You can designate elevators to be express elevators by setting stopsAtFloor[i] to be FALSE for floors where this elevator does not stop. Passengers will only enter cars that will stop at their intended destination. You can change the stopsAtFloor values at any time, but you need to be careful not to strand passengers -- you can command the car to stop at any time, but the door will only open at floor i if stopsAtFloor[i] is TRUE.

The objective of this Challenge is to deliver passengers to their destinations as expeditiously as possible. You incur a cost of one point for each passenger for each time step from the time s/he presses the call button until the time s/he exits the elevator. You also incur one point for each 10 milliseconds of execution time, including the time spent by AdvanceTime. Stranding a passenger inside an elevator or not responding to an elevator call button results in disqualification of your solution. The solution that incurs the fewest points wins the Challenge. There are no storage constraints for this Challenge, except that it must execute on my 96MB 8500/200.

The Challenge will simulate a normal workday in our simulated skyscraper. People arrive at the beginning of the day either by entering the parking garage at floor 0 or by walking into the main entrance at floor 1. They work in approximately equal numbers on floors 2 through numFloors-1. During the day, they move about the building as necessary. Somewhere in the middle of the day, most of them take a lunch break, either at the cafeteria on floor 2 or by leaving the building. Nearly everyone leaves the building at the end of the day. However, as advanced as our elevators are, they don't have a clock, so you'll have to establish your strategy without knowing the time of day.

This will be a native PowerPC Challenge, using the latest CodeWarrior environment. Solutions may be coded in C, C++, or Pascal. Ernst Munter wins two Challenge points for suggesting this problem, way back in November, 1996.

### Three Months Ago Winner

Congratulations to Sebastian Maurer for submitting the winning entry to the April Mancala Challenge. Sebastian won a round-robin tournament whose object was to efficiently capture the most stones in a variant of the ancient game of Mancala. In our variant of the game, the number of bowls ranged from 8 to 32, instead of the traditional 14, and players were allowed to move in either the clockwise or counter-clockwise directions. Congratulations also to JG Heithcock, whose solution actually captured more stones than Sebastian's did, but used better than 50% more execution time to do so. Both of the top solutions used an alpha-beta minmax technique to identify the best move, but Sebastian's heuristic for pruning the tree, combined with the time penalty of one stone per 100ms of execution time, gave him the higher overall score. Sebastian gained a little extra efficiency by partitioning his code into two parallel versions, one for playing first and another for playing second.

Twelve people submitted Mancala solutions, and eleven of those solutions participated in the tournament. (One solution occasionally made illegal moves, so it was eliminated to avoid unevenly affecting the scores of the other players.) The tournament consisted of seven test cases, with board sizes of 8, 12, 16, 20, 24, 28, and 32 bowls. Each solution played against each other solution twice in each test case, once playing first, and once playing second. The top solutions all used some variant of the minmax algorithm, while the lower ranking solutions used simpler heuristics, like always favoring moves that dropped the last stone into their mancala.

The table below lists the results of the tournament, with the solutions ranked in order of total points earned. It lists total execution time for the tournament, the total number of stones captured, the solution rank if execution time had been ignored, total points earned, as well as code size, data size, and programming language used. As usual, 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 Time (secs) Cum Stones Rank (stones) Cum Points Code Size Data Size Lang Sebastian Maurer (10) 54.16 14764 2 14222.40 3488 136 C JG Heithcock 85.37 14897 1 14043.26 1784 48 C++ Ken Krugler 97.45 14627 3 13652.46 4288 308 C++ Randy Boring (73) 59.90 14055 4 13456.02 8048 824 C Eric Kenninga 21.10 13399 5 13187.99 14584 894 C++ Willeke Rieken (47) 3.63 11667 6 11630.74 4088 8 C++ Simon Jensen-Fellows 0.33 11512 7 11508.68 3364 6147 C, Res Dennis Jones (10) 2.76 10383 9 10355.41 2556 125 C++ Eric Hangstefer (9) 0.05 10252 10 10251.54 3724 124 C Ernst Munter (362) 104.76 11178 8 10130.42 7916 13 C++ Josh Cooley 0.27 9446 11 9443.29 2228 64 C K. H. 0.00 Errors 12 0.00 3772 104 C++

### Top Contestants

Here are the Top Contestants for the Programmer's Challenge, including everyone who has accumulated more than 10 points during the past two years. The numbers below include points awarded over the 24 most recent contests, including points earned by this month's entrants.

1. Munter, Ernst 210 points
2. Boring, Randy 70 points
3. Cooper, Greg 61 points
4. Mallett, Jeff 50 points
5. Rieken, Willeke 47 points
6. Nicolle, Ludovic 34 points
7. Lewis, Peter 31 points
8. Maurer, Sebastian 30 points
9. Gregg, Xan 24 points
10. Murphy, ACC 24 points
11. Hart, Alan 21 points
12. Antoniewicz, Andy 20 points
13. Day, Mark 20 points
14. Higgins, Charles 20 points
15. Hostetter, Mat 20 points
16. Studer, Thomas 20 points

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 Sebastian's winning solution to the Mancala Challenge:

Mancala.C

```#include <stdio.h>
#include "Mancala.h"

enum { kDefault, kPlayAgain, kGameOver };
typedef long StateOfGame;

// There are two versions of almost every routine
// so we don't have to decide at run time
// which side to play on. It speeds things up a
// little bit
// AlphaBeta1 and AlphaBeta2 are the recursive searchers
// for each of the two players. They return the value of
// best move (returned in *chosenBowl, *chosenDirection).
// For a description of Minimax and Alphabeta searches,
// see Peter Norvig's
// "Paradigms of Artificial Intelligence Programming"

#define kMaxSignedLong    0x7FFFFFFF

Prototypes
long AlphaBeta1(
long depth,
long board[],
long *boardStorage,
const long boardSize,
long *chosenBowl,
long *chosenDirection,
long lowerBound,
/* any big negative number to enter recursion */
long upperBound
/* any big positive number to enter recursion */
);

long AlphaBeta2(
long depth,
long board[],
long *boardStorage,
const long boardSize,
long *chosenBowl,
long *chosenDirection,
long lowerBound,
long upperBound
);

// DropStones -- play the move
// Return true if we get to play again

Boolean DropStones1(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
);

Boolean DropStones2(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
);

// SideEmpty returns true if the side is empty
// (and the game is over)

Boolean FirstSideEmpty(
long board[],
const long halfBoardSize
);

Boolean SecondSideEmpty(
long board[],
const long boardSize
);
// Moves all the remaining stones
// to the appropriate Mancala

void RemainingToMancala(
long board[],
const long boardSize,
const Boolean playerOne
);

// DoMove Drops the stones, checks if the game
// is over (if so, cleans up the board), and
// returns kGameOver, kPlayAgain, or kDefault
StateOfGame DoMove1(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
);

StateOfGame DoMove2(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
);

// Called only once from
// within Mancala
Boolean ClaimingVictory(
long board[],
const long boardSize,
const Boolean playerOne
);

Mancala
Boolean Mancala(        /* return true if claiming victory */
long board[]          /* on entry, board[i] is number of stones in bowl i */
/* on exit, board reflects the results of your move */
const long boardSize,  /* number of bowls in the board, including mancalas */
void *privStorage,    /* pointer to 1MB of storage for your use */
const Boolean newGame,  /* true for your first move of a game */
const Boolean playerOne,  /* true when you are the first player */
long *bowlPlayed,        /* return the number of the bowl you played from */
long *directionPlayed    /* return 1 if you played counter-clockwise, */
/* return -1 if you played clockwise */
)
{
#pragma unused(newGame)
// Q&D way to decide how far to search
// so that we don't lose too much time
long depth;
switch (boardSize)
{
case 8: depth = 10; break;
case 10: depth = 8; break;
case 12:
case 14: depth = 6; break;
case 16:
case 18: depth = 5; break;
case 20:
case 22:
case 24:
case 26: depth = 4; break;
case 28:
case 30:
case 32: depth = 3; break;
default: depth = 1; break;
}

// Start recursion and play move
if (playerOne) {
AlphaBeta1(depth, board, (long*)privStorage,
boardSize, bowlPlayed, directionPlayed,
-kMaxSignedLong, kMaxSignedLong);
DropStones1(board, boardSize,
*bowlPlayed, *directionPlayed);
}
else
{
AlphaBeta2(depth, board, (long*)privStorage,
boardSize, bowlPlayed, directionPlayed,
-kMaxSignedLong, kMaxSignedLong);
DropStones2(board, boardSize,
*bowlPlayed, *directionPlayed);
}

// Correct to proper convention
*directionPlayed = - (*directionPlayed);
return ClaimingVictory(board, boardSize, playerOne);
}

AlphaBeta1
long AlphaBeta1(
long depth,
long board[],
long *boardStorage,
const long boardSize,
long *chosenBowl,
long *chosenDirection,
long lowerBound,
long upperBound
)
{
long myMancala, hisMancala, firstBowl, halfBoardSize;
long bowl, dir, value, bestBowl, bestDir;
long *workingBoard;

halfBoardSize = boardSize / 2;
workingBoard = boardStorage + depth * boardSize;
myMancala = 0;
hisMancala = halfBoardSize;
firstBowl = 1;

for (bowl = firstBowl; bowl < hisMancala; bowl++)
if (board[bowl] > 0)
{
StateOfGame result;
long i;

dir = -1;

// The following trick speeds the whole program
// up by about 1 percent... take it or leave it
for (i = 0; i < halfBoardSize; i++)
((double*)workingBoard)[i] =
((double*)board)[i];

result = DoMove1(workingBoard, boardSize,
bowl, dir);
if ((depth == 0) || (result == kGameOver))
value = workingBoard[myMancala] -
workingBoard[hisMancala];
else
{
if (result == kPlayAgain)
value = AlphaBeta1(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
lowerBound, upperBound);
else
value = - AlphaBeta2(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
- upperBound, - lowerBound);
}

if (value > lowerBound)
{
bestBowl = bowl;
bestDir = dir;
lowerBound = value;

if (lowerBound >= upperBound)
break;
}

dir = 1;

for (i = 0; i < halfBoardSize; i++)
((double*)workingBoard)[i] =
((double*)board)[i];

result = DoMove1(workingBoard, boardSize, bowl, dir);
if ((depth == 0) || (result == kGameOver))
value = workingBoard[myMancala] -                   workingBoard[hisMancala];
else
{
if (result == kPlayAgain)
value = AlphaBeta1(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
lowerBound, upperBound);
else
value = - AlphaBeta2(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
- upperBound, - lowerBound);
}

if (value > lowerBound)
{
bestBowl = bowl;
bestDir = dir;
lowerBound = value;

if (lowerBound >= upperBound)
break;
}

}

*chosenBowl = bestBowl;
*chosenDirection = bestDir;
return lowerBound;
}

AlphaBeta2
long AlphaBeta2(
long depth,
long board[],
long *boardStorage,
const long boardSize,
long *chosenBowl,
long *chosenDirection,
long lowerBound,
long upperBound
)
{
long myMancala, hisMancala, firstBowl, halfBoardSize;
long bowl, dir, value, bestBowl, bestDir;
long *workingBoard;

halfBoardSize = boardSize / 2;

workingBoard = boardStorage + depth * boardSize;
myMancala = halfBoardSize;
hisMancala = 0;
firstBowl = myMancala + 1;
for (bowl = firstBowl; bowl < boardSize; bowl++)
if (board[bowl] > 0)
{
long i, result;

dir = -1;

for (i = 0; i < halfBoardSize; i++)
((double*)workingBoard)[i] =
((double*)board)[i];

result = DoMove2(workingBoard, boardSize,
bowl, dir);
if ((depth == 0) || (result == kGameOver))
value = workingBoard[myMancala] -
workingBoard[hisMancala];
else
{
if (result == kPlayAgain)
value = AlphaBeta2(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
lowerBound, upperBound);
else
value = - AlphaBeta1(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
- upperBound, - lowerBound);
}
if (value > lowerBound)
{
bestBowl = bowl;
bestDir = dir;
lowerBound = value;
if (lowerBound >= upperBound)
break;
}

dir = 1;

for (i = 0; i < halfBoardSize; i++)
((double*)workingBoard)[i] =
((double*)board)[i];

result = DoMove2(workingBoard, boardSize,
bowl, dir);
if ((depth == 0) || (result == kGameOver))
value = workingBoard[myMancala] -
workingBoard[hisMancala];
else
{
if (result == kPlayAgain)
value = AlphaBeta2(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
lowerBound, upperBound);
else
value = - AlphaBeta1(
depth - 1, workingBoard,
boardStorage, boardSize,
chosenBowl, chosenDirection,
- upperBound, - lowerBound);
}

if (value > lowerBound)
{
bestBowl = bowl;
bestDir = dir;
lowerBound = value;
if (lowerBound >= upperBound)
break;
}

}

*chosenBowl = bestBowl;
*chosenDirection = bestDir;
return lowerBound;
}

DropStones1
/***
Boolean DropStones()
Drops stones, return true if we get to play again
***/

inline Boolean DropStones1(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
)
{
long myMancala, hisMancala, firstBowl, lastBowl;
long stonesInHand, nextBowl;

myMancala = 0;
hisMancala = boardSize / 2;
firstBowl = 1;
lastBowl = hisMancala - 1;

stonesInHand = board[bowlPlayed];
board[bowlPlayed] = 0;
nextBowl = bowlPlayed;
/* Drop stones */
while (stonesInHand > 0) {
nextBowl += directionPlayed;

if (nextBowl == hisMancala)
nextBowl += directionPlayed;
else
{
if (nextBowl < 0)
nextBowl = boardSize - 1;
else
if (nextBowl == boardSize)
nextBowl = 0;
}
board[nextBowl] += 1;
stonesInHand -= 1;
}

/* Perform capture */
if ((board[nextBowl] == 1) &&
(nextBowl >= firstBowl) &&
(nextBowl <= lastBowl))
{
board[nextBowl] = 0;
board[myMancala] +=
(1 + board[boardSize - nextBowl]);
board[boardSize - nextBowl] = 0;
}

/* Return true if get to play again */
return (nextBowl == myMancala);
}

DropStones2
inline Boolean DropStones2(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
)
{
long myMancala, firstBowl, lastBowl;
long stonesInHand, nextBowl;

myMancala = boardSize / 2;
firstBowl = myMancala + 1;
lastBowl = boardSize - 1;

stonesInHand = board[bowlPlayed];
board[bowlPlayed] = 0;
nextBowl = bowlPlayed;
/* Drop stones */
while (stonesInHand > 0) {
nextBowl += directionPlayed;

if (nextBowl <= 0)
nextBowl = boardSize - 1;
else
if (nextBowl == boardSize)
nextBowl = 1;
board[nextBowl] += 1;
stonesInHand -= 1;
}

/* Perform capture */
if ((board[nextBowl] == 1) &&
(nextBowl >= firstBowl) &&
(nextBowl <= lastBowl))
{
board[nextBowl] = 0;
board[myMancala] +=
(1 + board[boardSize - nextBowl]);
board[boardSize - nextBowl] = 0;
}

/* Return true if get to play again */
return (nextBowl == myMancala);
}

FirstSideEmpty
/*
Boolean FirstSideEmpty()
Checks to see if first side has no stones left in it
*/
inline Boolean FirstSideEmpty(
long board[],
const long halfBoardSize
)
{
long bowl;
for(bowl = halfBoardSize - 1; bowl > 0; bowl--)
if (board[bowl] != 0)
return false;
return true;
}

SecondSideEmpty
/*
Boolean SecondSideEmpty()
Checks to see if first side has no stones left in it
*/
inline Boolean SecondSideEmpty(
long board[],
const long boardSize
)
{
long bowl;
long halfBoardSize = boardSize / 2;
for(bowl = boardSize - 1; bowl > halfBoardSize; bowl--)
if (board[bowl] != 0)
return false;
return true;
}

RemainingToMancala
/*
void RemainingToMancala()
Moves remaining stones on specified side into Mancala
*/
inline void RemainingToMancala(
long board[],
const long boardSize,
const Boolean playerOne
)
{
long mancala, firstBowl, lastBowl, bowl;

if (playerOne) {
mancala = 0;
firstBowl = 1;
lastBowl = boardSize / 2 - 1;
} else {
mancala = boardSize / 2;
firstBowl = boardSize / 2 + 1;
lastBowl = boardSize - 1;
}

for(bowl = firstBowl; bowl <= lastBowl; bowl++)
{
board[mancala] += board[bowl];
board[bowl] = 0;
}
}

DoMove1
/***
StateOfGame DoMove()
Drops the specified stones and cleans up the board
if the game is over.
***/

inline StateOfGame DoMove1(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
)
{
Boolean getToPlayAgain;

getToPlayAgain = DropStones1(board, boardSize,
bowlPlayed, directionPlayed);

if (FirstSideEmpty(board, boardSize / 2)) {
RemainingToMancala(board, boardSize, false);
return kGameOver;
}

if (SecondSideEmpty(board, boardSize)) {
RemainingToMancala(board, boardSize, true);
return kGameOver;
}

if (getToPlayAgain)
return kPlayAgain;
else
return kDefault;
}

DoMove2
inline StateOfGame DoMove2(
long board[],
const long boardSize,
long bowlPlayed,
long directionPlayed
)
{
Boolean getToPlayAgain;

getToPlayAgain = DropStones2(board, boardSize,
bowlPlayed, directionPlayed);

if (FirstSideEmpty(board, boardSize / 2)) {
RemainingToMancala(board, boardSize, false);
return kGameOver;
}

if (SecondSideEmpty(board, boardSize)) {
RemainingToMancala(board, boardSize, true);
return kGameOver;
}

if (getToPlayAgain)
return kPlayAgain;
else
return kDefault;
}

ClaimingVictory
/* Boolean ClaimingVictory()
Only called before returning from Mancala
Does not clean up the board
*/
Boolean ClaimingVictory(
long board[],
const long boardSize,
const Boolean playerOne
)
{
long bowl;
long sum = 0;
long halfBoardSize = boardSize / 2;

if (FirstSideEmpty(board, halfBoardSize))
{
for (bowl = halfBoardSize + 1;
bowl < boardSize; bowl++)
sum += board[bowl];
if (playerOne)
return board[0] > (sum + board[halfBoardSize]);
else
return board[0] < (sum + board[halfBoardSize]);
}
if (SecondSideEmpty(board, boardSize))
{
for (bowl = 1; bowl < halfBoardSize; bowl++)
sum += board[bowl];
if (playerOne)
return (board[0] + sum) > board[halfBoardSize];
else
return (board[0] + sum) < board[halfBoardSize];
}
return false;
}
```

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Alto's Odyssey 1.0.1 Device: iOS Universal Category: Games Price: \$4.99, Version: 1.0.1 (iTunes) Description: Just beyond the horizon sits a majestic desert, vast and unexplored. Join Alto and his friends and set off on an endless... | Read more »
Vainglory 5v5: Everything you need to kn...
Check out these 5 games that are a lot l...
So you're in love with Minecraft, but you're looking for something else to play as well? You've come to the right place then, because this list is all about games that are a bit like Minecraft. Some of them, more than others. [Read more] | Read more »
Our top 5 characters from casual RPG Cre...
Creature Quest definitely lives up to its name with a host of collectible creatures based on fantasy tales and world mythologies. To celebrate Creature Questâ€™s first birthday, weâ€™re going to lay out what we think are the five best characters in the... | Read more »
Around the Empire: What have you missed...
Did you know that Steel Media has a whole swathe of other sites dedicated to all aspects of mobile gaming? Sure you'll get the very best iPhone news, reviews, and opinions right here at 148Apps, but we don't want you missing out on a single piece... | Read more »
All the best games on sale for iPhone an...
Oh hi there, and welcome to our round-up of the best games that are currently on sale for iPhone and iPad. You thought I didn't see you there, did you, skulking behind the bushes? Trust me though, the bushes aren't where the best deals are. The... | Read more »
The Battle of Polytopia Guide - How to H...
A new update just released for The Battle of Polytopia (formerly Super Tribes), which introduces online multiplayer. For all the fans of Midjiwanâ€™s lite take on Civilization, this is certainly welcome news, but playing online isnâ€™t as easy and... | Read more »

## Price Scanner via MacPrices.net

Amazon restocks MacBook Pros with models avai...
Amazon has restocked 15â€³ and 13â€³ Apple MacBook Pros with models on sale for up to \$251 off MSRP. Shipping is free. Note that stock of some Macs may come and go (and some sell out quickly), so check... Read more
Lowest price of the year: 15â€³ 2.8GHz Apple Ma...
Amazon has the 2017 Space Gray 15â€³ 2.8GHz MacBook Pro on sale today for \$251 off MSRP. Shipping is free: â€“ 15â€³ 2.8GHz Touch Bar MacBook Pro Space Gray (MPTR2LL/A): \$2148, \$251 off MSRP Their price is... Read more
Apple restocks full line of Certified Refurbi...
Apple has restocked a full line of Apple Certified Refurbished 2017 13â€³ MacBook Pros for \$200-\$300 off MSRP. A standard Apple one-year warranty is included with each MacBook, and shipping is free.... Read more
Lowest sale price available for 13â€³ 1.8GHz Ma...
Focus Camera has the 2017 13â€³ 1.8GHz/128GB Apple MacBook Air on sale today for \$829 including free shipping. Their price is \$170 off MSRP, and itâ€™s the lowest price available for a current 13â€³... Read more
21-inch 2.3GHz iMac on sale for \$999, \$100 of...
B&H Photo has the 2017 21â€³ 2.3GHz iMac (MMQA2LL/A) in stock and on sale for \$999 including free shipping plus NY & NJ tax only. Their price is \$100 off MSRP. Read more
Apple refurbished Mac minis in stock again st...
Apple has restocked Certified Refurbished Mac minis starting at \$419. Appleâ€™s one-year warranty is included with each mini, and shipping is free: â€“ 1.4GHz Mac mini: \$419 \$80 off MSRP â€“ 2.6GHz Mac... Read more
Tuesday MacBook Deals: \$250 off 15â€³ 2.9GHz Ma...
Adorama has the Silver 15â€³ 2.9GHz Apple MacBook Pro on sale today for \$250 off MSRP. Shipping is free, and Adorama charges sales tax for residents in NY & NJ only: â€“ 15â€³ 2.9GHz Silver MacBook Pro... Read more
Save up to \$350 with these Apple Certified Re...
Apple has a full line of Certified Refurbished iMacs available for up to \$350 off original MSRP. Appleâ€™s one-year warranty is standard, and shipping is free. The following models are available: â€“ 27... Read more
B&H offers \$200 discount on Silver 15â€³ Ma...
B&H Photo has Silver 15â€³ Apple MacBook Pros on sale for \$200 off MSRP. Shipping is free, and B&H charges sales tax for NY & NJ residents only: â€“ 15â€³ 2.8GHz Touch Bar MacBook Pro Silver (... Read more
12â€³ Apple iPad Pro Sale of the Year! Models u...
B&H Photo has 12â€³ #iPad Pros on sale for up to \$150 off MSRP. Shipping is free, and B&H charges sales tax in NY & NJ only: â€“ 12â€³ 64GB WiFi iPad Pro: \$719 \$80 off MSRP â€“ 12â€³ 256GB WiFi... Read more

## Jobs Board

*Apple* Retail - Multiple Positions - Apple,...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Solutions Consultant - Apple (United...
# Apple Solutions Consultant Job Number: 113523441 Orange, CA, California, United States Posted: 21-Feb-2018 Weekly Hours: 40.00 **Job Summary** Are you passionate Read more
*Apple* Retail - Multiple Positions - Apple,...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Sr. Experience Designer, Today at *Apple* -...
# Sr. Experience Designer, Today at Apple Job Number: 56495251 Santa Clara Valley, California, United States Posted: 18-Jan-2018 Weekly Hours: 40.00 **Job Summary** Read more