Nov 97 Challenge

Volume Number: 13 (1997)
Issue Number: 11
Column Tag: Programmer's Challenge

by Bob Boonstra, Westford, MA

Pente®

Reaching once again into the closet where we store board games, I found the game of Pente®, The board physically resembles the board used in GO, but the game strategies are simpler. Pente® is played by two players who alternate placing stones on a 19x19 grid. The objective is to win the game by getting five or more stones in a row or, alternatively, by capturing five or more pairs of your opponent's stones. Your Challenge is to write code that will play the game of Pente® and accumulate the most points (described below) in the minimum time. The prototype for the code you should write is:

```typedef struct Capture {
Point stone1;
Point stone2;
} Capture;

void InitPente(
long boardHalfSize        /* e.g., 9 for a 19x19 board */
/* all coordinates between -boardHalfSize
and +boardHalfSize */
);

void Pente(
Point opponentsMove,    /* your opponent moved here */
Boolean playingFirst,    /* ignore opponentMove */
Point *yourMove,        /* return your move here */
Capture claimCaptures[],  /* return coordinates of captured pairs here */
long *numCaptures,      /* return number of claimCaptures here */
Boolean *claimVictory    /* return true if you claim victory with this move */
);

void TermPente(void);        /* deallocate any dynamic storage */```

Captures take place by bracketing two adjacent stones of your opponents. Given the position

`---BWW---`

... Black can capture the two White stones by playing ...

`---BWWB--`

... after which the two White stones are removed ...

`---B B--`

Captures can occur horizontally, vertically, or diagonally. Note that no capture occurs if White moves into the unoccupied square below:

`---BW-B--`

Three Months Ago Winner

Congratulations to Peter Lewis (Perth, Australia) for submitting the winning entry to the Stratego Challenge. Peter's entry was a convincing winner in a tournament of the 5 entries submitted. The Stratego tournament consisted of 80 games, with each entry playing against each other entry 8 times, 4 times playing first and 4 times playing second. Peter's entry plays a very good game of Stratego, as evidenced by the fact that it won 30 of the 32 games it played. His algorithm, described in the commentary at the beginning of his code, includes aggressively attempting to capture weaker pieces, exploring with low ranking pieces of his own, running away from stronger pieces, exchanging pieces of equal rank, and advancing toward unknown pieces. Of the 30 games Peter's entry won, 10 were won by capturing the opponent's flag, and 19 were won by eliminating all of the pieces that the opponent could move. (The remaining win resulted from resignation of the opponent.) Several of the entries used delaying tactics in an attempt to take advantage of the scoring rules and force their opponent to earn negative points for a win. As discussed on the Challenge mailing list, I cut off games where one player took longer than 20 seconds, declared a tie, and awarded points (sometimes negative points) to each player. The table below lists the tournament results and point totals 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     Code    Data     Language
Peter Lewis (37)    30          296.62    13436     310       C++
Dennis Jones        13           86.75     8632     414        C
Randy Boring (39)    5           58.68     5724     618        C
Ernst Munter (286)   9           29.45    12044    4072       C++
Tom Saxton (10)      7          -51.69     7320     460        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.

```  Rank       Name       Points    Rank         Name           Points
1.    Munter, Ernst     200      11.   Antoniewicz, Andy      24
2.    Gregg, Xan         63      12.   Picao, Miguel Cruz     21
3.    Lewis, Peter       57      13.       Day, Mark          20
4.    Cooper, Greg       54      14.    Higgins, Charles      20
5.    Boring, Randy      41      15.     Studer, Thomas       20
6.    Lengyel, Eric      40      16.       Saxton, Tom        17
7.    Mallett, Jeff      30      17.      Gundrum, Eric       15
8.    Murphy, ACC        30      18.        Hart, Alan        14
9.    Nicolle, Ludovic   28      19     O'Connor, Turlough    14
10.   Larsson, Gustav   27      20.       Karsh, Bill        12
```

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 Peter's winning solution:

Challenge.cp

© 1997 Peter N Lewis

```#define ASSERTIONS 0
#define DEBUG_RULES 0

#include Timer.h
#include stdlib.h
#include string.h

#include "Challenge.h"

/*
Author: Peter N Lewis

Assumptions:
Only time we spend thinking is counted against out 10 seconds (not time
in GetMove/ReportMove)
[Actually, this assumption is not valid, but Peter won anyway. --Bob]

Method:
Basically we keep track of the board and what we know and what they know.
Each opponent piece has a bit map associated with it describing what pieces
it could be. As we see more pieces, the bit map is culled. If the piece
moves, the bomb & flag bits are removed. If we've seen all Scouts
(for example), then the Scout bit is removed from all remaining pieces. If
all but one bit is remvoed, then we know what the piece is.

At each turn, we simply apply a sequence of actions (listed below) and
take the first action that works. It does very little in the way of
lookahead (it plans out a path, but doesn't remember it and doesn't take
it to account any movement by the opposition)

It keeps a CRC of recent board positions (since the last strike) and doesn't
replay any boards (we want to win, not draw!).

If we exceed 10 seconds thinking time, we resign. Not that this is particularly
likely, in the games I tried, it spend less than half a second total.

Optimizations:
None.

Comment:
It actually plays a half decent game! The end game is not as good as I'd
like, but time is up!
*/

/*
USE SPY
If our spy is next to their 1, kill it

DEFEND AGAINST SPY
if we have seen the spy, ignore this case

If an unknown piece is next to the 1, then run, attack, have another piece attack,
or ignore depending on a table

ATTACK WEAKER
If a known piece is next to a weaker known piece, attack it except if it places
that piece in a dangerous location

EXPLORE ATTACK
If a 6,7,9 is next to an unknown piece, attack it

RETREAT
If a known piece is next to a stronger known piece, run away (preferably
towards something that can kill it or if it's lowly, towards an unknown piece)

SCOUT
Try advancing scouts rapidly

ATTACK DISTANT
If a known piece is distant, but a clear path leads a slightly better piece
towards it, advance the better piece (includes miners)

EXPLORE DISTANT
Try exploring (advance lowly pieces towards unknown pieces)

ATTACK KNOWN WITH SAME DISTANT
If a known piece can be attacked by a known identical piece, attack it

FIND FLAG
When few unmoved pieces remain, start assuming they are bombs/flags

MOVE FORWARD
Move any piece we can forward

MOVE
Move any piece we can

RESIGN
Give up
*/

#if ASSERTIONS

static void Assert( short must )
{
if ( !must ) {
DebugStr( "\pAssert failed!\n" );
}
}

#else

#define Assert( must )

#endif

enum {
kEmpty = kFlag+1,
kWater,
kMoved,        // fake rank for moved pieces
kAddForRankish  // add this in for enemies when calculating the CRC
};

enum {
kNoColor = 0
};

enum {
kNoNothing = 0x00001FFE,
kStationaryBits = ((1 << kBomb) | (1 << kFlag))
};

enum {
kRepeatedBoards = 1000
};

typedef struct Square {
PlayerColor color;
PieceRank rank;
UInt32 possibilities;
} Square;

typedef Square OurBoard[kBoardSize][kBoardSize];

typedef int Counts[kFlag+1];

typedef UInt32 BoardPossibilities[kBoardSize][kBoardSize];

typedef struct Storage {
UInt32 total_time;
UInt32 extra_time;
OurBoard board;
Counts our_pieces;
Counts their_pieces;
Boolean do_getmove;
Boolean victory;
Square blankSquare;
PlayerColor playerColor;
PlayerColor theirColor;
BoardPossibilities dangers;
BoardPossibilities known_dangers;
UInt32 repeated_board[kRepeatedBoards];
UInt32 repeated_board_count;
} Storage, *StoragePtr;

static char *board_setup[4] = {
// 1 = Marshal, ..., 9 = Scout, : = Spy, ; = Bomb, < = Flag
"8;<;67;7;7",
"48;3862;89",
"6359954865",
"997159:499",
};

static char *start_piece_counts = "0112344458161";

static int dR[4] = { 1, 0, -1, 0 };
static int dC[4] = { 0, -1, 0, 1 };

#if ASSERTIONS

AssertValidBoard
static void AssertValidBoard( StoragePtr storage )
{
int piece;
int count1 = 0;
int count2 = 0;
int row, col;

for ( piece = kMarshall; piece <= kFlag; piece++ ) {
count1 += storage->their_pieces[piece];
}

for ( row = 0; row < kBoardSize; row++ ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( storage->board[row][col].color == storage->theirColor
&& storage->board[row][col].rank == kUnknown ) {
count2++;
}
}
}

Assert( count1 == count2 );
}

#else

#define AssertValidBoard( storage )

#endif

PositionPieces
void PositionPieces(
void *privStorage,        /* 1MB of preinitialized storage for your use */
PlayerColor playerColor,    /* you play red or blue, with red playing first */
Board *theBoard            /* provide the initial position of your pieces */
)
{
StoragePtr storage = (StoragePtr) privStorage;
int row, our_row, their_row, col, board_col;
PlayerColor theirColor;
int piece;
Boolean reverse = (TickCount() & 1) != 0;

Assert( strlen(board_setup[0]) == kBoardSize );
Assert( strlen(board_setup[1]) == kBoardSize );
Assert( strlen(board_setup[2]) == kBoardSize );
Assert( strlen(board_setup[3]) == kBoardSize );

for ( row = 0; row <= 3; row++ ) {
if ( playerColor == kRed ) {
our_row = row;
their_row = (kBoardSize-1)-row;
theirColor = kBlue;
} else {
their_row = row;
our_row = (kBoardSize-1)-row;
theirColor = kRed;
}
for ( col = 0; col < 10; col++ ) {
board_col = reverse ? (kBoardSize-1) - col : col;
(*theBoard)[our_row][col].thePieceRank = (PieceRank)
(board_setup[row][board_col] - '0');
(*theBoard)[our_row][col].thePieceColor = playerColor;

storage->board[our_row][col].color = playerColor;
storage->board[our_row][col].rank =
(*theBoard)[our_row][col].thePieceRank;
storage->board[our_row][col].possibilities = kNoNothing;

storage->board[their_row][col].color = theirColor;
storage->board[their_row][col].rank = kUnknown;
storage->board[their_row][col].possibilities = kNoNothing;
}
}

for ( row = 4; row <= 5; row++ ) {
for( col = 0; col < kBoardSize; col++ ) {
storage->board[row][col].color = (PlayerColor)kNoColor;
storage->board[row][col].rank =
(PieceRank) ((col/2 % 2 == 1) ? kWater : kEmpty);
storage->board[row][col].possibilities = 0;
}
}

for ( piece = kMarshall; piece <= kFlag; piece++ ) {
storage->our_pieces[piece] =
start_piece_counts[piece] - '0';
storage->their_pieces[piece] =
start_piece_counts[piece] - '0';
}

storage->do_getmove = (playerColor == kBlue);
storage->victory = false;
storage->blankSquare = storage->board[4][0];
storage->playerColor = playerColor;
storage->theirColor = playerColor == kRed ? kBlue : kRed;
storage->repeated_board_count = 0;

AssertValidBoard( storage );
}

Learn
static void Learn( StoragePtr storage, Boolean them,
int row, int col, PieceRank rank )
{
Boolean gotall;
PlayerColor thiscolor;
int r, c;

if ( storage->board[row][col].rank == kUnknown ) {

if ( rank == kMoved ) {
UInt32 possibilities =
storage->board[row][col].possibilities;
possibilities &= ~kStationaryBits;

if ( (possibilities & (possibilities-1)) == 0 ) {
// only one bit on! Now we know!
int newrank;
newrank = 0;
while ( (possibilities & 1) == 0 ) {
possibilities >>= 1;
newrank++;
}
rank = (PieceRank)newrank;
} else {
storage->board[row][col].possibilities = possibilities;
}
}

if ( rank != kMoved ) {
storage->board[row][col].rank = rank;
storage->board[row][col].possibilities = (1 << rank);
if ( them ) {
gotall = --storage->their_pieces[rank] == 0;
} else {
gotall = --storage->our_pieces[rank] == 0;
}
if ( gotall ) {
thiscolor = storage->board[row][col].color;
for ( r = 0; r < kBoardSize; r++ ) {
for ( c = 0; c < kBoardSize; c++ ) {
if ( storage->board[r][c].rank == kUnknown
&& storage->board[r][c].color == thiscolor ) {
UInt32 possibilities =
storage->board[r][c].possibilities;
possibilities &= ~ (1 << rank);
storage->board[r][c].possibilities = possibilities;
if ( (possibilities & (possibilities-1)) == 0 ) {
// only one bit on!
int newrank;
newrank = 0;
while ( (possibilities & 1) == 0 ) {
possibilities >>= 1;
newrank++;
}
Learn( storage, them, r, c, (PieceRank)newrank );
}
}
}
}
}
}
} else {
Assert( rank == kMoved ||
storage->board[row][col].rank == rank );
}
}

HandleTheirMove
static void HandleTheirMove( StoragePtr storage,
GetOpponentMove GetMove )
{
PiecePosition moveFrom;
PiecePosition moveTo;
Boolean moveStrike;
MoveResult moveResult;
UnsignedWide start, finish;

Microseconds( &start );
(*GetMove)( &moveFrom,&moveTo, &moveStrike,&moveResult );
Microseconds( &finish );
storage->extra_time += finish.lo - start.lo;

Assert( moveResult.legalMove );
// They must have made a legal move or we would not be called
Assert( !moveResult.victory );
// If they won we would not be called
if ( moveStrike ) {
Learn( storage, true, moveFrom.row, moveFrom.col,
moveResult.rankOfAttacker.thePieceRank );
Learn( storage, false, moveTo.row, moveTo.col,
moveResult.rankOfDefender.thePieceRank );
if ( moveResult.attackerRemoved &&
moveResult.defenderRemoved ) {
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
storage->board[moveTo.row][moveTo.col] =
storage->blankSquare;
} else if ( moveResult.attackerRemoved ) {
if (storage->board[moveTo.row][moveTo.col].rank == kBomb) {
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
} else {
storage->board[moveFrom.row][moveFrom.col] =
storage->board[moveTo.row][moveTo.col];
storage->board[moveTo.row][moveTo.col] =
storage->blankSquare;
}
} else {
Assert( moveResult.defenderRemoved );
storage->board[moveTo.row][moveTo.col] =
storage->board[moveFrom.row][moveFrom.col];
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
}
} else {
storage->board[moveTo.row][moveTo.col] =
storage->board[moveFrom.row][moveFrom.col];
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
if ( abs(moveTo.row - moveFrom.row) +
abs(moveTo.col - moveFrom.col) > 1 ) {
Learn( storage, true, moveTo.row, moveTo.col, kScout );
} else {
Learn( storage, true, moveTo.row, moveTo.col,
(PieceRank)kMoved );
}
}

AssertValidBoard( storage );
}

FindPiece
static Boolean FindPiece( StoragePtr storage, PlayerColor color,
PieceRank rank, int *row, int *col )
{
int r, c;

for ( r = 0; r < kBoardSize; r++ ) {
for( c = 0; c < kBoardSize; c++ ) {
if ( storage->board[r][c].color == color
&& storage->board[r][c].rank == rank ) {
*row = r;
*col = c;
return true;
}
}
}
return false;
}

IsOnBoardWeak
static Boolean IsOnBoardWeak( int row, int col )
{
return  0 <= row && row < kBoardSize &&
0 <= col && col < kBoardSize;
}

IsOnBoard
static Boolean IsOnBoard( int row, int col )
{
if (   0 <= row && row < kBoardSize &&
0 <= col && col < kBoardSize ) {
if ( row <= 3 || row >= 6 ) {
return true;
}
if ( col <= 1 || col >= 8 ) {
return true;
}
if ( 4 <= col && col <= 5 ) {
return true;
}
}
return false;
}

IsColorPiece
static Boolean IsColorPiece( StoragePtr storage,
int row, int col, PlayerColor color )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].color == color;
}

IsOurPiece
static Boolean IsOurPiece( StoragePtr storage, int row, int col )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].color == storage->playerColor;
}

IsTheirPiece
static Boolean IsTheirPiece( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].color == storage->theirColor;
}

IsUnknownPiece
static Boolean IsUnknownPiece( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].rank == kUnknown;
}

IsRankPiece
static Boolean IsRankPiece( StoragePtr storage,
int row, int col, PieceRank rank )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].rank == rank;
}

IsEmptySquare
static Boolean IsEmptySquare( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].rank == (PieceRank)kEmpty;
}

IsWaterSquare
static Boolean IsWaterSquare( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoardWeak( row, col ) );
return storage->board[row][col].rank == (PieceRank)kWater;
}

IsLowlyRank
static Boolean IsLowlyRank( PieceRank rank )
{
return kCaptain <= rank && rank <= kScout && rank != kMiner;
}

IsLowlyPiece
static Boolean IsLowlyPiece( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoard( row, col ) );
return IsLowlyRank( storage->board[row][col].rank );
}

IsMovedPiece
static Boolean IsMovedPiece( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoard( row, col ) );
return (storage->board[row][col].possibilities &
kStationaryBits) == 0;
}

IsRevealedPiece
static Boolean IsRevealedPiece( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoard( row, col ) );
Assert( IsOurPiece( storage, row, col ) );
UInt32 possibilities = storage->board[row][col].possibilities;
return ( (possibilities & (possibilities-1)) == 0 );
}

static int CountAdjacentUnknownPieces( StoragePtr storage,
PlayerColor color, int row, int col )
{
int d;
int unknowns = 0;

for ( d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c ) && IsColorPiece( storage, r, c,           color )
&& IsUnknownPiece( storage, r, c ) ) {
unknowns++;
}
}

return unknowns;
}

static char *defend_spy_table = "RARROAOORARRRARRXAXAOAOOXAXAXAXA";
// Run/Attack/Other/Nothing, >1 unknown:other:danger:moved

LowlyCanAttack
static Boolean LowlyCanAttack( StoragePtr storage, int row,
int col, int *otherRow, int *otherCol )
{
for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c )
&& IsOurPiece( storage, r, c )
&& IsLowlyPiece( storage, r, c ) ) {
*otherRow = r;
*otherCol = c;
return true;
}
}
return false;
}

UpdateDangerPossibilities
static void UpdateDangerPossibilities( StoragePtr storage )
{
int row, col;

for ( row = 0; row < kBoardSize; row++ ) {
for( col = 0; col < kBoardSize; col++ ) {
storage->dangers[row][col] = 0;
storage->known_dangers[row][col] = 0;
}
}
for ( row = 0; row < kBoardSize; row++ ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsTheirPiece( storage, row, col ) ) {
UInt32 possibilities =
(storage->board[row][col].possibilities &
~kStationaryBits);
UInt32 known_possibilities = 0;

if ( storage->board[row][col].rank != kUnknown ) {
known_possibilities = possibilities;
}

for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c ) ) {
storage->dangers[r][c] |= possibilities;
storage->known_dangers[r][c] |= known_possibilities;
}
}
}
}
}
}

GetDangerPossibilities
static UInt32 GetDangerPossibilities( StoragePtr storage,
int row, int col )
{
Assert( IsOnBoard( row, col ) );
return storage->dangers[row][col];
}

PossibilitiesCouldKill
static Boolean PossibilitiesCouldKill( PieceRank rank,
UInt32 possibilities )
{
if ( (possibilities & ~kStationaryBits) == 0 ) {
return false;
}

switch ( rank ) {
case kFlag:
return true;
case kBomb:
return (possibilities & (1 << kMiner)) != 0;
case kMarshall:
return (possibilities & ((1 << kMarshall) + (1<< kSpy)))
!= 0;
default:
return (possibilities & ((1 << (rank+1)) - 1)) != 0;
}
}

PossibilitiesCouldKillSafely
static Boolean PossibilitiesCouldKillSafely( PieceRank rank,
UInt32 possibilities )
{
if ( (possibilities & ~kStationaryBits) == 0 ) {
return false;
}

switch ( rank ) {
case kFlag:
return true;
case kBomb:
return (possibilities & (1 << kMiner)) != 0;
case kMarshall:
return (possibilities & ((1<< kSpy))) != 0;
default:
return (possibilities & ((1 << rank) - 1)) != 0;
}
}

WillKillPossibilities
static Boolean WillKillPossibilities( PieceRank rank,
UInt32 possibilities )
{
Assert( possibilities != 0 );

switch ( rank ) {
case kFlag:
return false;
case kBomb:
return false;
case kMiner:
return (possibilities & ~((1 << kScout) + (1 << kBomb) +
(1 << kFlag))) == 0;
case kSpy:
return (possibilities & ~(1 << kMarshall)) == 0;
default:
return (possibilities & (((1 << (rank + 1)) - 1) +
(1 << kBomb))) == 0;
}
}

WillKillOrSuicidePossibilities
static Boolean WillKillOrSuicidePossibilities( PieceRank rank,
UInt32 possibilities )
{
Assert( possibilities != 0 );

switch ( rank ) {
case kFlag:
return false;
case kBomb:
return false;
case kMiner:
return (possibilities & ~((1 << kScout) + (1 << kMiner) +
(1 << kBomb) + (1 << kFlag))) == 0;
case kSpy:
return (possibilities & ~((1 << kMarshall) + (1 << kSpy)))
== 0;
default:
return (possibilities & (((1 << rank) - 1) + (1 << kBomb)))
== 0;
}
}

WillPossibilitiesKill
static Boolean WillPossibilitiesKill( UInt32 possibilities,
PieceRank rank )
{
Assert( possibilities != 0 );
possibilities &= ~kStationaryBits;
if ( possibilities == 0 ) {
return false;
}

switch ( rank ) {
case kFlag:
return true;
case kBomb:
return possibilities == (1 << kMiner);
default:
return (possibilities & ~((1 << (rank+1))-1)) == 0;
}
}

FindSafeSquare
static Boolean FindSafeSquare( StoragePtr storage, int row,
int col, int *safeRow, int *safeCol )
{
Assert( IsOnBoard( row, col ) );

PieceRank rank = storage->board[row][col].rank;
int doff = (storage->playerColor == kBlue ? 0 : 2);
// Try backwards first

for ( int d = 0; d < 4; d++ ) {
int dr = dR[(d + doff) % 4];
int dc = dC[(d + doff) % 4];
int r = row + dr;
int c = col + dc;

while ( IsOnBoard( r, c ) &&
IsEmptySquare( storage, r, c ) ) {
if ( !PossibilitiesCouldKill( rank,
GetDangerPossibilities( storage, r, c ) ) ) {
*safeRow = r;
*safeCol = c;
return true;
}
if ( rank != kScout ) {
break;
}
r += dr;
c += dc;
}
}
return false;
}

CountEnemies
static void CountEnemies( StoragePtr storage, int row, int col,
int *knowns, int *unknowns )
{
*knowns = 0;
*unknowns = 0;

for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c ) && IsTheirPiece( storage, r, c ) ) {
if ( storage->board[r][c].rank == kUnknown ) {
*unknowns += 1;
} else {
*knowns += 1;
}
}
}
}

/*
static Boolean CanRun( StoragePtr storage, int row, int col, int *runRow, int *runCol )
{
for ( int d = 0; d < 4; d++ ) {
int r = row +
dR[(d + (storage->playerColor == kBlue ? 0 : 2)) % 4];
// Try backwards first
int c = col +
dC[(d + (storage->playerColor == kBlue ? 0 : 2)) % 4];

if ( IsOnBoard( r, c ) &&
(storage->board[r][c].rank == kEmpty) ) {
*runRow = r;
*runCol = c;
return true;
}
}
return false;
}
*/

FindSafePath
static Boolean FindSafePath( StoragePtr storage,
Boolean very_safe, Boolean suicide_ok, int from_row,
int from_col, int to_row, int to_col, int *best_path,
int *first_row, int *first_col )
{
Assert( IsOurPiece( storage, from_row, from_col ) );

PieceRank rank = storage->board[from_row][from_col].rank;
BoardPossibilities *dangers =
very_safe ? &storage->dangers : &storage->known_dangers;

if (   abs( from_row - to_row ) +
abs( from_col - to_col ) > *best_path ) {
return false;
}

if ( abs( from_row - to_row ) +
abs( from_col - to_col ) == 1 ) {
*best_path = 0;
*first_row = to_row;
*first_col = to_col;
return true;
}

int path_length_to[kBoardSize][kBoardSize];
PiecePosition que[kBoardSize * kBoardSize];
int que_start = 0;
int que_fin = 0;
int que_next_len = 0;
int current_len = 0;
int row, col;

for ( row = 0; row < kBoardSize; row++ ) {
for( col = 0; col < kBoardSize; col++ ) {
path_length_to[row][col] = -1;
}
}

que[que_fin].row = from_row;
que[que_fin].col = from_col;
path_length_to[from_row][from_col] = 0;
que_fin++;
que_next_len = que_fin;

while ( que_fin > que_start ) {
row = que[que_start].row;
col = que[que_start].col;
que_start++;

for ( int d = 0; d < 4; d++ ) {
int dr = dR[d];
int dc = dC[d];
// scout moves NYI
int r = row + dr;
int c = col + dc;

if ( IsOnBoard( r, c ) && path_length_to[r][c] == -1
&& IsEmptySquare( storage, r, c ) ) {
if ( suicide_ok ?
!PossibilitiesCouldKillSafely( rank, (*dangers)[r][c] )
: !PossibilitiesCouldKill( rank, (*dangers)[r][c]    ) ) {
path_length_to[r][c] = current_len + 1;
if ( abs( to_row - r ) + abs( to_col - c ) == 1 ) {
*best_path = current_len + 1;
while ( current_len > 0 ) {
for ( int d = 0; d < 4; d++ ) {
int backr = r + dR[d];
int backc = c + dC[d];

if ( path_length_to[backr][backc] == current_len ) {
r = backr;
c = backc;
break;
}
}
current_len--;
}
*first_row = r;
*first_col = c;
return true;
}
que[que_fin].row = r;
que[que_fin].col = c;
que_fin++;
} else {
path_length_to[r][c] = 1000; // Cant go here
}
}
}

if ( que_start == que_next_len ) {
que_next_len = que_fin;
current_len++;
}
}

return false;
}

CalcBoardCRC
static UInt32 CalcBoardCRC( StoragePtr storage,
int from_row, int from_col, int to_row, int to_col )
{
Assert( !IsOnBoard( from_row, from_col ) ||
IsOurPiece( storage, from_row, from_col ) );
Assert( !IsOnBoard( to_row, to_col ) ||
IsEmptySquare( storage, to_row, to_col ) );

UInt32 result = 0;

int row, col;
int rankish;

for ( row = 0; row < kBoardSize; row++ ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( row == from_row && col == from_col ) {
rankish = 0;
} else if ( row == to_row && col == to_col ) {
rankish = storage->board[from_row][from_col].rank;
} else if ( IsEmptySquare( storage, row, col ) ||
IsWaterSquare( storage, row, col ) ) {
rankish = 0;
} else if ( IsOurPiece( storage, row, col ) ) {
rankish = storage->board[row][col].rank;
} else {
rankish = storage->board[row][col].rank + kAddForRankish;
}
result += rankish; // Hmm, not a very good CRC
result = result * 11 + (result >> 25);
}
}

return result;
}

OKMove
static Boolean OKMove( StoragePtr storage, int from_row, int from_col,
int to_row, int to_col )
{
if ( IsTheirPiece( storage, to_row, to_col ) ) {
return true;
}

UInt32 crc = CalcBoardCRC( storage, from_row, from_col,
to_row, to_col );
long i;
for ( i = 0; i < storage->repeated_board_count; i++ ) {
if ( crc == storage->repeated_board[i] ) {
return false;
}
}
return true;
}

AppendRepeatedBoard
static void AppendRepeatedBoard( StoragePtr storage )
{
UInt32 crc = CalcBoardCRC( storage, -1, -1, -1, -1 );

if ( storage->repeated_board_count == kRepeatedBoards ) {
storage->repeated_board_count--;
BlockMoveData( &storage->repeated_board[1],
&storage->repeated_board[0],
storage->repeated_board_count *
sizeof(storage->repeated_board[0]) );
}
storage->repeated_board[storage->repeated_board_count++] = crc;
}

#if DEBUG_RULES
#define RETURN( x ) DebugStr( x ";g" ); return
#else
#define RETURN( x ) return
#endif

FigureOutOurMove
static void FigureOutOurMove( StoragePtr storage,
PiecePosition *moveFrom, PiecePosition *moveTo )
{
int ourRow, ourCol,theirRow,theirCol,row,col,runRow,runCol;
int rowFirst = storage->playerColor == kRed ?
0 : kBoardSize - 1;
int rowLast = storage->playerColor == kRed ?
kBoardSize - 1 : 0;
int rowAdd = storage->playerColor == kRed ? 1 : -1;
int bestUnknowns;
int bestPath;
int thisPath;

UpdateDangerPossibilities( storage );

// USE SPY
if ( FindPiece( storage, storage->theirColor, kMarshall,
&theirRow, &theirCol )
&& FindPiece( storage, storage->playerColor, kSpy,
&ourRow, &ourCol )
&& abs( theirRow - ourRow ) +
abs( theirCol - ourCol ) == 1 ) {
moveFrom->row = ourRow;
moveFrom->col = ourCol;
moveTo->row = theirRow;
moveTo->col = theirCol;
RETURN( "\pUSE SPY" );
}
```
```// DEFEND AGAINST SPY
if (storage->their_pieces[kSpy] > 0) {
if ( FindPiece( storage, storage->playerColor, kMarshall,
&ourRow, &ourCol ) ) {
int unknowns = CountAdjacentUnknownPieces( storage,
storage->theirColor, ourRow, ourCol );

if ( unknowns ) {
char todo = 0; // R = Run, A = Attack, O = Attack with Other
int base_index = 0;
Boolean canrun = FindSafeSquare( storage, ourRow, ourCol,
&runRow, &runCol );
if ( !canrun ) {
base_index += 16;
}
if ( unknowns > 1 ) {
base_index += 8;
}

for ( int d = 0; d < 4; d++ ) {
int r = ourRow + dR[d];
int c = ourCol + dC[d];
int otherRow, otherCol;

if ( IsOnBoard( r, c )
&& IsTheirPiece( storage, r, c )
&& IsUnknownPiece( storage, r, c ) ) {
int index = base_index;
if ( LowlyCanAttack( storage, r, c,
&otherRow, &otherCol ) ) {
index += 4;
}
if ( CountAdjacentUnknownPieces( storage,
storage->theirColor, r, c ) > 0 ) {
index += 2;
}
if ( IsMovedPiece( storage, r, c ) ) {
index += 1;
}

if ( defend_spy_table[index] == 'A' ) { // Attack
moveFrom->row = ourRow;
moveFrom->col = ourCol;
moveTo->row = r;
moveTo->col = c;
RETURN( "\pDEFEND AGAINST SPY 1" );
} else if ( defend_spy_table[index] == 'O' ) { // Attack
moveFrom->row = otherRow;
moveFrom->col = otherCol;
moveTo->row = r;
moveTo->col = c;
RETURN( "\pDEFEND AGAINST SPY 2" );
}
}
}

if ( canrun && OKMove( storage, ourRow, ourCol,
runRow, runCol ) ) {
moveFrom->row = ourRow;
moveFrom->col = ourCol;
moveTo->row = runRow;
moveTo->col = runCol;
RETURN( "\pDEFEND AGAINST SPY 3" );
}
// Give up! Next rule...
}
}
}

// ATTACK WEAKER
for ( row = rowFirst; 0 <= row && row < kBoardSize;
row += rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsTheirPiece( storage, row, col ) ) {
UInt32 enemy = storage->board[row][col].possibilities;
UInt32 danger = GetDangerPossibilities( storage,
row, col );

int bestDir = -1;
Boolean isBestRevealed = true;
PieceRank bestRank = kUnknown;

for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c ) && IsOurPiece( storage, r, c ) ) {
if ( !PossibilitiesCouldKill(
storage->board[r][c].rank, danger ) ) {
if ( WillKillPossibilities(
storage->board[r][c].rank, enemy ) ) {
Boolean thisRevealed =
IsRevealedPiece( storage, r, c );
if ( isBestRevealed || !thisRevealed ) {
if ( bestDir == -1 ||
(storage->board[r][c].rank > bestRank) ) {
bestDir = d;
bestRank = storage->board[r][c].rank;
isBestRevealed = thisRevealed;
}
}
}
}
}
}
if ( bestDir != -1 ) {
moveFrom->row = row + dR[bestDir];
moveFrom->col = col + dC[bestDir];
moveTo->row = row;
moveTo->col = col;
RETURN( "\pATTACK WEAKER" );
}
}
}
}

// EXPLORE ATTACK
for ( int rnk = kScout; rnk >= kMarshall; rnk-- ) {
PieceRank rank = (PieceRank) rnk;
if ( IsLowlyRank( rank ) ) {

for ( row = rowLast; 0 <= row && row < kBoardSize;
row -= rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsOurPiece( storage, row, col )
&& IsRankPiece( storage, row, col, rank ) ) {

for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c )
&& IsTheirPiece( storage, r, c )
&& IsRankPiece( storage, r, c, kUnknown ) ) {
moveFrom->row = row;
moveFrom->col = col;
moveTo->row = r;
moveTo->col = c;
RETURN( "\pEXPLORE ATTACK" );
}
}
}
}
}
}
}

// RETREAT
for ( row = rowLast; 0 <= row && row < kBoardSize;
row -= rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsOurPiece( storage, row, col )
&& IsMovedPiece( storage, row, col ) ) {

for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c )
&& IsTheirPiece( storage, r, c )
&& WillPossibilitiesKill(
storage->board[r][c].possibilities,
storage->board[row][col].rank ) ) {
bestPath = 1000;
for ( int to_row = rowLast; 0 <= to_row &&
to_row < kBoardSize; to_row -= rowAdd ) {
for( int to_col = 0; to_col < kBoardSize; to_col++ ) {
thisPath = bestPath;
if ( IsTheirPiece( storage, to_row, to_col )
&& (IsRankPiece( storage, to_row, to_col,
kUnknown )
|| WillKillPossibilities(
storage->board[row][col].rank,
storage->board[to_row][to_col].possibilities ))
&& FindSafePath( storage, false, true, row, col,
to_row, to_col, &thisPath, &runRow, &runCol )
&& OKMove( storage, row, col, runRow, runCol ) ) {
bestPath = thisPath;
moveFrom->row = row;
moveFrom->col = col;
moveTo->row = runRow;
moveTo->col = runCol;
}
}
}
if ( bestPath < 1000 ) {
RETURN( "\pRETREAT" );
}
}
}
}
}
}

// SCOUT
bestUnknowns = 0;

for ( row = rowLast; 0 <= row && row < kBoardSize;
row -= rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsOurPiece( storage, row, col )
&& IsRankPiece( storage, row, col, kScout ) ) {
for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

while ( IsOnBoard( r, c ) &&
IsEmptySquare( storage, r, c ) ) {

int knowns, unknowns;
CountEnemies( storage, r, c, &knowns, &unknowns );
if ( knowns == 0 && unknowns > bestUnknowns &&
OKMove( storage, row, col, r, c ) ) {
bestUnknowns = unknowns;
ourRow = row;
ourCol = col;
runRow = r;
runCol = c;
}
r += dR[d];
c += dC[d];
}
}
}
}
}

if ( bestUnknowns > 0 ) {
moveFrom->row = ourRow;
moveFrom->col = ourCol;
moveTo->row = runRow;
moveTo->col = runCol;
RETURN( "\pSCOUT" );
}

// ATTACK DISTANT

bestPath = 1000;

for ( row = rowFirst; 0 <= row && row < kBoardSize;
row += rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsTheirPiece( storage, row, col ) ) {
UInt32 possibilities =
storage->board[row][col].possibilities;
UInt32 danger =
GetDangerPossibilities( storage, row, col );

if ( (possibilities & ((1 << kBomb) | (1 << kMarshall))) !=
((1 << kBomb) | (1 << kMarshall)) ) {
for ( int r = rowFirst; 0 <= r && r < kBoardSize;
r += rowAdd ) {
for( int c = 0; c < kBoardSize; c++ ) {
if ( IsOurPiece( storage, r, c ) ) {
if ( WillKillPossibilities(
storage->board[r][c].rank, possibilities ) ) {
if ( storage->board[r][c].rank >= kCaptain ||
!PossibilitiesCouldKill(
storage->board[r][c].rank, danger ) ) {
thisPath = bestPath;
if ( FindSafePath( storage, true, false, r, c,
row, col, &thisPath, &runRow, &runCol ) ) {
if ( OKMove( storage, r, c, runRow, runCol ) ) {
bestPath = thisPath;
moveFrom->row = r;
moveFrom->col = c;
moveTo->row = runRow;
moveTo->col = runCol;
}
}
}
}
}
}
}
}

}
}
}

if ( bestPath < 1000 ) {
RETURN( "\pATTACK DISTANT" );
}

// EXPLORE DISTANT

bestPath = 1000;

for ( row = rowFirst; 0 <= row && row < kBoardSize;
row += rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsTheirPiece( storage, row, col ) &&
storage->board[row][col].rank == kUnknown ) {

for ( int r = rowFirst; 0 <= r && r < kBoardSize;
r += rowAdd ) {
for( int c = 0; c < kBoardSize; c++ ) {
if ( IsOurPiece( storage, r, c ) &&
IsLowlyPiece( storage, r, c ) ) {
thisPath = bestPath;
if ( FindSafePath( storage, false, true, r, c,
row, col, &thisPath, &runRow, &runCol ) ) {
if ( OKMove( storage, r, c, runRow, runCol ) ) {
bestPath = thisPath;
moveFrom->row = r;
moveFrom->col = c;
moveTo->row = runRow;
moveTo->col = runCol;
}
}
}
}
}

}
}
}

if ( bestPath < 1000 ) {
RETURN( "\pEXPLORE DISTANT" );
}

// ATTACK KNOWN WITH SAME DISTANT

bestPath = 1000;

for ( row = rowFirst; 0 <= row && row < kBoardSize;
row += rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsTheirPiece( storage, row, col ) ) {
UInt32 possibilities =
storage->board[row][col].possibilities;

if ( (possibilities & ((1 << kBomb) | (1 << kMarshall))) !=
((1 << kBomb) | (1 << kMarshall)) ) {
for ( int r = rowFirst; 0 <= r && r < kBoardSize;
r += rowAdd ) {
for( int c = 0; c < kBoardSize; c++ ) {
if ( IsOurPiece( storage, r, c ) ) {
if ( WillKillOrSuicidePossibilities(
storage->board[r][c].rank, possibilities ) ) {
thisPath = bestPath;
if ( FindSafePath( storage, true, true, r, c,
row, col, &thisPath, &runRow, &runCol ) ) {
if ( OKMove( storage, r, c, runRow, runCol ) ) {
bestPath = thisPath;
moveFrom->row = r;
moveFrom->col = c;
moveTo->row = runRow;
moveTo->col = runCol;
}
}
}
}
}
}
}

}
}
}

if ( bestPath < 1000 ) {
RETURN( "\pATTACK KNOWN WITH SAME DISTANT" );
}

// FIND FLAG
// NYI

// MOVE FORWARD

for ( row = rowLast; 0 <= row && row < kBoardSize; row -= rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsOurPiece( storage, row, col ) ) {
PieceRank rank = storage->board[row][col].rank;
if ( rank != kBomb && rank != kFlag ) {
int r = row + rowAdd;
if ( IsOnBoard( r, col ) && !IsOurPiece( storage, r, col ) &
& OKMove( storage, row, col, r, col ) ) {
moveFrom->row = row;
moveFrom->col = col;
moveTo->row = r;
moveTo->col = col;
RETURN( "\pMOVE FORWARD" );
}
}
}
}
}

// MOVE

for ( row = rowLast; 0 <= row && row < kBoardSize;
row -= rowAdd ) {
for( col = 0; col < kBoardSize; col++ ) {
if ( IsOurPiece( storage, row, col ) ) {
PieceRank rank = storage->board[row][col].rank;
if ( rank != kBomb && rank != kFlag ) {

for ( int d = 0; d < 4; d++ ) {
int r = row + dR[d];
int c = col + dC[d];

if ( IsOnBoard( r, c ) &&
!IsOurPiece( storage, r, c ) &&
OKMove( storage, row, col, r, c ) ) {
moveFrom->row = row;
moveFrom->col = col;
moveTo->row = r;
moveTo->col = c;
RETURN( "\pMOVE" );
}
}
}
}
}
}

// RESIGN
moveFrom->row = -1;
moveFrom->col = -1;
moveTo->row = -1;
moveTo->col = -1;
RETURN( "\pRESIGN" );

}

HandleOurMove
static void HandleOurMove( StoragePtr storage,
ReportYourMove ReportMove )
{
PiecePosition moveFrom;
PiecePosition moveTo;
Boolean moveStrike;
MoveResult moveResult;
UnsignedWide start, finish;

if ( storage->total_time > 10000000 ) { // Time to give up
// Resign
moveFrom.row = -1;
moveFrom.col = -1;
moveTo.row = -1;
moveTo.col = -1;
} else {
FigureOutOurMove( storage, &moveFrom, &moveTo );
}
if ( IsOnBoard( moveTo.row, moveTo.col ) ) {
moveStrike = storage->board[moveTo.row][moveTo.col].color !=
kNoColor;
} else {
moveStrike = false;
}

Microseconds( &start );
(*ReportMove)( &moveFrom, &moveTo, moveStrike, &moveResult );
Microseconds( &finish );
storage->extra_time += finish.lo - start.lo;

if ( moveResult.victory ) {       // We Win! :-)
storage->victory = true;
} else if ( !moveResult.legalMove ) {   // We Lose! :-(
} else {
if ( moveStrike ) {
storage->repeated_board_count = 0;
Learn( storage, true, moveTo.row, moveTo.col,
moveResult.rankOfDefender.thePieceRank );
Learn( storage, false, moveFrom.row, moveFrom.col,
moveResult.rankOfAttacker.thePieceRank );

if ( moveResult.attackerRemoved &&
moveResult.defenderRemoved ) {
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
storage->board[moveTo.row][moveTo.col] =
storage->blankSquare;
} else if ( moveResult.attackerRemoved ) {
if ( storage->board[moveTo.row][moveTo.col].rank==kBomb ) {
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
} else {
storage->board[moveFrom.row][moveFrom.col] =
storage->board[moveTo.row][moveTo.col];
storage->board[moveTo.row][moveTo.col] =
storage->blankSquare;
}
} else {
Assert( moveResult.defenderRemoved );
storage->board[moveTo.row][moveTo.col] =
storage->board[moveFrom.row][moveFrom.col];
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
}

} else {
if ( abs( moveTo.row - moveFrom.row ) +
abs( moveTo.col - moveFrom.col ) > 1 ) {
Assert( storage->board[moveFrom.row][moveFrom.col].rank ==
kScout );
Learn( storage, false, moveFrom.row, moveFrom.col, kScout);
} else {
Learn( storage, false, moveFrom.row, moveFrom.col,
(PieceRank)kMoved );
}
storage->board[moveTo.row][moveTo.col] =
storage->board[moveFrom.row][moveFrom.col];
storage->board[moveFrom.row][moveFrom.col] =
storage->blankSquare;
}
AppendRepeatedBoard( storage );
}

AssertValidBoard( storage );
}

MakeAMove
Boolean MakeAMove(
void *privStorage,      /* 1MB of storage from PositionPieces */
PlayerColor playerColor,    /* you play red or blue, with red playing first */
GetOpponentMove *GetMove,  /* callback used to find about opponents last move*/
ReportYourMove *ReportMove  /* callback used to make a move */
)
{
StoragePtr storage = (StoragePtr) privStorage;
UnsignedWide start, finish;

storage->extra_time = 0;
Microseconds( &start );

if ( storage->do_getmove ) {
HandleTheirMove( storage, *GetMove );
}
storage->do_getmove = true;

HandleOurMove( storage, *ReportMove );

Microseconds( &finish );
storage->total_time +=
finish.lo - start.lo - storage->extra_time;

return storage->victory;
}
```

CHALLENGE.H

```#ifndef __LL_CHALLENGE__
#define __LL_CHALLENGE__

#ifdef __cplusplus
extern "C" {
#endif

#define kBoardSize 10

typedef enum { kUnknown=0,
kMarshall=1,kGeneral,kColonel,kMajor,kCaptain,
kLieutenant,kSergeant,kMiner,kScout,kSpy,
kBomb,kFlag
} PieceRank;

typedef enum {kRed=1,kBlue=2} PlayerColor;

typedef struct PieceType {
PieceRank  thePieceRank;     /* rank of a piece */
PlayerColor thePieceColor;    /* color of a piece */
} PieceType;

typedef PieceType Board[kBoardSize][kBoardSize];
/* Used to provide test code with board configuration. Red starts
in rows 0..3, Blue starts in rows 6..9 */
/* Squares [4][2], [4][3], [4][6], [4][7] and
[5][2], [5][3], [5][6], [5][7] are water and cannot
be occupied */

typedef struct PiecePosition {
long row; /* 0..9 */
long col; /* 0..9 */
} PiecePosition;

typedef struct MoveResult {
PieceType rankOfAttacker;
/* after a strike, returns identity of attacker */
PieceType rankOfDefender;
/* after a strike, returns identity of defender */
Boolean attackerRemoved;
/* true after a strike against a piece of equal or greater rank,
or against a bomb when the attacker is not a Miner */
Boolean defenderRemoved;
/* true after a strike by a piece of equal or greater rank,
or against a bomb when the attacker is a Miner,
or against a Marshall by a Spy */
Boolean victory;
/* true after a strike against the Flag */
Boolean legalMove;
/* true unless you
- move into an occupied square, or
- move or strike in a direction other than forward, backward, or sideways, or
- move more than one square (except Scouts), or
- move a Bomb or a Flag,
- move into Water, or
- strike a square not occupied by an opponent, or
- make any other illegal move */
} MoveResult;

void PositionPieces(
void *privStorage,      /* 1MB of preinitialized storage for your use */
PlayerColor playerColor,  /* you play red or blue, with red playing first */
Board *theBoard        /* provide the initial position of your pieces */
);

typedef void (*ReportYourMove)(
/* Callback to inform test code of move and
get results */
PiecePosition *moveFrom,  /* piece you are moving or using to strike */
PiecePosition *moveTo,    /* destination square or square being struck */
Boolean strike,          /* false indicates a move, true indicates a strike */
MoveResult *results      /* returns identity of struck piece and other info */
);

typedef void (*GetOpponentMove)(
/* Callback to get results of opponents last move */
PiecePosition *moveFrom,    /* piece opponent moved or used to strike */
PiecePosition *moveTo,      /* destination square or square struck */
Boolean *strike,           /* false indicates a move, true indicates a strike */
MoveResult *results       /* returns identity of struck piece and other info */
);

Boolean MakeAMove(
void *privStorage,        /* 1MB of storage from PositionPieces */
PlayerColor playerColor,   /* you play red or blue, with red playing first */
GetOpponentMove *GetMove,   /* callback used to find about opponents last move */
ReportYourMove *ReportMove  /* callback used to make a move */
);

#ifdef __cplusplus
}
#endif

#endif                ```

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Spotify 1.2.0.1165 - Stream music, creat...
Spotify is a streaming music service that gives you on-demand access to millions of songs. Whether you like driving rock, silky R&B, or grandiose classical music, Spotify's massive catalogue puts... Read more
Thunderbird 102.5.1 - Email client from...
As of July 2012, Thunderbird has transitioned to a new governance model, with new features being developed by the broader free software and open source community, and security fixes and improvements... Read more
Pinegrow 7.03 - Mockup and design web pa...
Pinegrow (was Pinegrow Web Designer) is desktop app that lets you mockup and design webpages faster with multi-page editing, CSS and LESS styling, and smart components for Bootstrap, Foundation,... Read more
Adobe After Effects 2022 23.1 - Create p...
The new, more connected Adobe After Effects can make the impossible possible. Get powerful new features like a Live 3D Pipeline that brings CINEMA 4D scenes in as layers - without intermediate... Read more
SteerMouse 5.6.7 - Powerful third-party...
SteerMouse is an advanced driver for USB and Bluetooth mice. SteerMouse can assign various functions to buttons that Apple's software does not allow, including double-clicks, modifier clicks,... Read more
Wireshark 4.0.2 - Network protocol analy...
Wireshark is one of the world's foremost network protocol analyzers, and is the standard in many parts of the industry. It is the continuation of a project that started in 1998. Hundreds of... Read more
Adobe Premiere Pro 2022 23.1 - Digital v...
Adobe Premiere Pro is available as part of Adobe Creative Cloud for as little as \$54.99/month. The price on display is a price for annual by-monthly plan for Adobe Premiere Pro only. Adobe Premiere... Read more
1Password is a password manager that uniquely brings you both security and convenience. It is the only program that provides anti-phishing protection and goes beyond password management by adding Web... Read more
FotoMagico 6.3 - Powerful slideshow crea...
FotoMagico lets you create professional slideshows from your photos and music with just a few, simple mouse clicks. It sports a very clean and intuitive yet powerful user interface. High image... Read more
Affinity Photo 1.10.6 - Digital editing...
Affinity Photo - redefines the boundaries for professional photo editing software for the Mac. With a meticulous focus on workflow it offers sophisticated tools for enhancing, editing and retouching... Read more

Latest Forum Discussions

‘Awaken Legends: Idle RPG’ Celebrates th...
Awaken Legends: Idle RPG is adding its first update since the game was soft-launched in November, letting players get their hands on a new hero “Hera Valen". Players can also look forward to the Covenant of the Dark Knight event and the Wishing Well... | Read more »
‘Horizon Chase 2’ Japan World Tour Expan...
Horizon Chase 2 () from Aquiris is getting a major expansion today on Apple Arcade. The Japan World Tour expansion brings in 11 new races across 9 cities and it should be rolling out now as of this writing. I expect it to be available worldwide... | Read more »
Dark Fantasy Visual Novel ‘The 13th Mont...
Originally announced for release in August, The 13th Month from Japanese developer Kobayashimaru and publisher Kodansha released on PC via Steam worldwide this month. The dark fantasy visual novel that reimagines the classic Sleeping Beauty tale, is... | Read more »
Tom Clancey’s The Divison Resurgence ann...
Ubisoft has announced the latest Live Test dates for Tom Clancy’s The Division Resurgence, the hotly anticipated mobile entry in the Divison series. Starting December 8th and ending on the 22nd, the test will offer a huge amount of content for the... | Read more »
‘Easy Come Easy Golf’ New Update Adds St...
Easy Come Easy Golf () from Clap Hanz is one of my favorite games on Apple Arcade. It has been updated quite a bit since launch bringing in new modes and improvements. It recently launched on Nintendo Switch as well. | Read more »
Out Now: ‘Magic vs Metal’, ‘Suzerain’, ‘...
Each and every day new mobile games are hitting the App Store, and so each week we put together a big old list of all the best new releases of the past seven days. Back in the day the App Store would showcase the same games for a week, and then... | Read more »
SwitchArcade Round-Up: Reviews Featuring...
Hello gentle readers, and welcome to the SwitchArcade Round-Up for December 7th, 2022. Today can be accurately described as Mikhail Madness, with a whopping four reviews from our pal-est of pals. Football Manager 2023 Touch, Wobbledogs, Soccer Story... | Read more »
Alchemy Stars celebrates 1 and a half ye...
It has been one and a half years since Alchemy Stars launched, and Level Infinite is celebrating in style with a host of new content. There will be a new story mission and even a store to explore, and a whole new mode for those budding idol... | Read more »
Fighting Game ‘Art of Fighting 2’ ACA Ne...
Last week, side-scrolling shooter Pulstar hit mobile platforms as the newest ACA NeoGeo series release from Hamster and SNK. Read Shaun’s review of it here. Today, fighting game Art of Fighting 2 has launched on iOS and Android. Art of Fighting 2... | Read more »
‘Genshin Impact’ Version 3.3 Update Now...
HoYoverse recently revealed the next major update for Genshin Impact (Free) in the form of version 3.3 ‘All Senses Clear, All Existence Void’. | Read more »

Price Scanner via MacPrices.net

New! Details on Verizon’s Christmas/Holiday p...
Verizon is offering discounts on iPhones, Apple Watch models, and iPads with specific promo codes as part of their Christmas/Holiday 2022 offerings. Codes are valid when adding a new line of service... Read more
Apple MagSafe accessories are back on Holiday...
Amazon has Apple MagSafe Chargers and Apple’s MagSafe Battery on sale for up to 24% off MSRP again as part of their Christmas/Holiday sale. Shipping is free, and all models are in stock: – MagSafe... Read more
13″ M2 MacBook Airs on sale again for the low...
Amazon has 13″ MacBook Airs with M2 CPUs in stock today and on sale for \$150 off MSRP as part of their Christmas/Holiday Sale, prices start at \$1049. Shipping is free. They are the lowest prices... Read more
Get an Apple 16″ MacBook Pro for \$400 off MSR...
16″ MacBook Pros with Apple’s M1 Pro CPUs are in stock and on sale today at B&H Photo for \$300-\$400 off Apple’s MSRP for a limited time. Prices start at \$2099 for M1 Pro models with 512GB or 1TB... Read more
Holiday clearance sale! Previous-generation A...
Amazon has 2nd generation 32GB and 64GB 4K Apple TVs with Siri remotes and 32GB Apple TV HDs on clearance sale for \$80-\$90 off original MSRP. Shipping is free, and delivery is available in time for... Read more
Christmas sale at Verizon: Apple AirPods Pro...
Verizon has first-generation Apple AirPods Pro on sale for \$159.99 on their online store as part of their continuing Christmas/Holiday sale. Their price is \$90 off Apple’s original MSRP, and it’s the... Read more
New Christmas/New Years promo at Xfinity Mobi...
Switch to Xfinity Mobile and open a new line of service, and take \$400 off the price of a new iPhone, no trade-in required, through January 10, 2023. The \$400 is applied to your account as credits... Read more
Apple iPad Smart Keyboard Folio prices drop u...
Apple iPad Smart Keyboard Folio prices have dropped up to \$60 off MSRP at Amazon and Walmart as part of their Christmas/Holiday sales. These are the cheapest prices currently available for these iPad... Read more
Today is the final day for Xfinity Mobile’s \$...
If you switch to Xfinity Mobile and open a new line of service, they will take \$500 off the price of a new iPhone, no trade-in required. This is the best no trade-in Cyber Monday Apple iPhone 14 deal... Read more
Amazon restocks 10.2″ 64GB 9th-generation iPa...
Amazon has Apple’s 9th generation 10.2″ 64GB WiFi iPads (Silver) in stock and on sale for \$269.99 shipped as part of their Christmas/Holiday Sale. Their price is \$60 off Apple’s MSRP. Free delivery... Read more

Jobs Board

*Apple* Systems Administrator - JAMF - Activ...
…Administration **Duties and Responsibilities** + Configure and maintain the client's Apple Device Management (ADM) solution. The current solution is JAMF supporting Read more
Cashier - *Apple* Blossom Mall - JCPenney (...
Cashier - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Blossom Mall Read more
Omnichannel Associate - *Apple* Blossom Mal...
Omnichannel Associate - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Read more
Sephora Beauty Advisor - *Apple* Blossom Ma...
Sephora Beauty Advisor - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Read more
Operations Associate - *Apple* Blossom Mall...
Operations Associate - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Read more
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