|
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--
Multiple captures can occur on a single move. The game ends when one side captures five pairs of the opponent's stones, or when one side places five stones in a straight line, either horizontally, vertically, or diagonally. When one side obtains an unblocked row of four stones, called a tessera, a win is imminent. Therefore, an unblocked row of three stones, called a tria, is a serious threat that should be blocked unless a stronger offensive move exists. To neutralize the advantage that the first player has, the first player's second move is restricted to be three or more intersections away from the center of the board (i.e., the h and v coordinates of White's second move must both be greater than or equal to 3 in absolute value). At the start of the game, your InitPente routine (and that of your opponent) will be called with the half-width of the board in boardHalfSize (between 9 and 15, inclusive). The Pente routines will then be alternately called, providing the location of your opponentsMove (unless you are playingFirst). You should place a stone in an unoccupied location and return that location in yourMove. In addition, if your move captures any adjacent pairs of your opponent's stones, you should report the number of captures in numCaptures, and the locations of the captured pairs in claimCaptures. If your move results in victory, either by achieving 5 of your stones in a row, or a cumulative capture of 5 pairs of your opponent's stones, you should set claimVictory to true. At the end of the game, TermPente will be called, where you should deallocate any dynamically allocated storage. Board coordinates are expressed as distance from the center square in ordered (v,h) pairs, so that the center intersection is at (0,0), and the corners of the standard board are at (-9,-9), (-9,9), etc. At the end of the game, points will be awarded as follows: 5 points for the player who achieved 5 stones in a row 1 point for each capture 1 point for each distinct sequence of 4 stones in a row remaining on the board One point will be deducted for each second of execution time used during a player's turns, including the time taken by the InitPente and TermPente routines. Both the game winner and the game loser will accumulate points. It is possible to earn negative points. The Challenge winner will be the entry that accumulates the most points in a round-robin tournament of all entries, where each entry plays each other entry at least twice, half of the time playing first and half playing second. Your code may allocate up to 10MB of dynamic storage, including both explicit calls to NewPtr/malloc and allocation of dynamic objects. This will be a native PowerPC Challenge, using the latest CodeWarrior environment. Solutions may be coded in C, C++, or Pascal. Pente® is published by Pente Games, Inc.
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 ); } CountAdjacentUnknownPieces 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
- SPREAD THE WORD:
- Slashdot
- Digg
- Del.icio.us
- Newsvine