/// <summary>
/// find next move by direct score
/// </summary>
/// <param name="x">current board</param>
/// <returns>next move</returns>
static public int DirectScoreMove(Board x)
{
double maxScore = 0;
int maxi = -1;
for (int k = 0; k < 4; k++)
{
if (BoardControl.ExecuteMove(x, k) == x)
{
continue;
}
if (PreScore.DirectScore(BoardControl.ExecuteMove(x, k)) > maxScore)
{
maxScore = PreScore.DirectScore(BoardControl.ExecuteMove(x, k));
maxi = k;
}
}
if (maxi == -1)
{
return(new Random(DateTime.Now.Millisecond).Next() % 4);
}
else
{
return(maxi);
}
}
/// <summary>
/// play game for monte carlo method
/// </summary>
/// <param name="Str">play strategy</param>
/// <param name="board">current board</param>
/// <param name="nmove">monte carlo steps</param>
/// <param name="move">pre-pointed next step</param>
/// <returns>score by monte carlo</returns>
public static double MontePlay(Strategy Str, Board board, int nmove, int move = -1)
{
bool first = true;
while (true)
{
UInt64 newboard;
if (first && (move != -1))
{
if (BoardControl.ExecuteMove(board, move) == board)
{
return(0);
}
first = false;
}
else
{
for (move = 0; move < 4; move++)
{
if (BoardControl.ExecuteMove(board, move) != board)
{
break;
}
}
if (move == 4)
{
break;
}
move = Str(board);
if (move < 0)
{
break;
}
}
newboard = BoardControl.ExecuteMove(board, move);
if (newboard == board)
{
continue;
}
UInt64 tile = BoardControl.RandomTile();
board = BoardControl.InsertTileRand(newboard, tile);
nmove--;
if (nmove <= 0)
{
return(PreScore.DirectScore(board));
}
}
return(0);
}
/// <summary>
/// play game by pointed strategy
/// </summary>
/// <param name="Str">play strategy</param>
public static void Play(Strategy Str)
{
Board board = BoardControl.InitBoard();
int moveno = 0;
int scorepenalty = 0;
while (true)
{
int move;
Board newboard;
for (move = 0; move < 4; move++)
{
if (BoardControl.ExecuteMove(board, move) != board)
{
break;
}
}
if (move == 4)
{
break;
}
BoardControl.Print(board);
System.Console.WriteLine("Move:" + (++moveno).ToString() + ", score:" + (BoardControl.Score(board) - scorepenalty).ToString() + '\n');
move = Str(board);
if (move < 0)
{
break;
}
newboard = BoardControl.ExecuteMove(board, move);
if (newboard == board)
{
System.Console.WriteLine("Illegal move!\n");
moveno--;
continue;
}
Board tile = BoardControl.RandomTile();
if (tile == 2)
{
scorepenalty += 4;
}
board = BoardControl.InsertTileRand(newboard, tile);
}
BoardControl.Print(board);
System.Console.WriteLine("\nGame over.\nScore:" + (BoardControl.Score(board) - scorepenalty).ToString() + ".\n");
}
/// <summary>
/// score while next process is move
/// </summary>
/// <param name="x">current board</param>
/// <param name="prob">current board probability</param>
/// <param name="para">parameters of search</param>
/// <returns>score</returns>
static double ScoreNextMove(UInt64 x, float prob, Param para)
{
double best = 0.0f;
UInt64 newboard;
para.depth++;
for (int d = 0; d < 4; ++d)
{
newboard = BoardControl.ExecuteMove(x, d);
if (x != newboard)
{
best = Math.Max(best, ScoreNextInsert(newboard, prob, para));
}
}
para.depth--;
return(best);
}
/// <summary>
/// score while next process is insert
/// </summary>
/// <param name="x">current board</param>
/// <param name="prob">current board probability</param>
/// <param name="para">parameters of search</param>
/// <returns>score</returns>
static double ScoreNextInsert(UInt64 x, float prob, Param para)
{
if (para.depth < DictionaryLimit)
{
if (para.scoreTable.ContainsKey(x))
{
return(para.scoreTable[x]);
}
}
if (prob < ProbTresh || para.depth >= para.depthLimit)
{
return(HeurScore(x));
}
int num = BoardControl.CountEmpty(x);
prob /= num;
double res = 0.0f;
UInt64 tmp = x;
UInt64 tile = 1;
while (tile != 0)
{
if ((tmp & 0xf) == 0)
{
res += ScoreNextMove(x | tile, prob * 0.9f, para) * 0.9f;
res += ScoreNextMove(x | (tile << 1), prob * 0.1f, para) * 0.1f;
}
tmp >>= 4;
tile <<= 4;
}
res = res / num;
if (para.depth < DictionaryLimit)
{
para.scoreTable[x] = res;
}
return(res);
}
/// <summary>
/// score board while pointed the next move
/// </summary>
/// <param name="x">current board</param>
/// <param name="d">pre-pointed next move</param>
/// <returns>score</returns>
public static double ScoreFirstMove(Board x, int d)
{
double res;
Param para = new Param();
para.scoreTable = new Dictionary <ulong, double>();
para.depthLimit = Math.Max(3, BoardControl.CountDistinctTiles(x) - 2);
UInt64 newboard = BoardControl.ExecuteMove(x, d);
if (x == newboard)
{
res = 0;
}
else
{
res = ScoreNextInsert(newboard, 1.0f, para) + 1e-6;
}
return(res);
}
/// <summary>
/// find next move by monte carlo method
/// </summary>
/// <param name="x">current board</param>
/// <returns>next move</returns>
static public int MonteCarloMove(Board x)
{
int iterN = 2000;
double[] score = new double[4] {
0, 0, 0, 0
};
double maxScore = 0;
int maxi = 0;
Parallel.For(0, 4, (i, loopState) =>
{
if (BoardControl.ExecuteMove(x, i) != x)
{
for (int j = 0; j < iterN; j++)
{
score[i] = score[i] + PlayGame.MontePlay(DirectScoreMove, x, 10, i);
}
}
});
for (int k = 0; k < 4; k++)
{
if (score[k] > maxScore)
{
maxScore = score[k];
maxi = k;
}
}
if (BoardControl.ExecuteMove(x, maxi) == x)
{
return(new Random(DateTime.Now.Millisecond).Next() % 4);
}
Console.WriteLine("Predict average score:" + (maxScore / iterN).ToString());
Console.WriteLine();
return(maxi);
}
static void Main(string[] args)
{
BoardControl.Initialize();
PreScore.Initialize();
PlayGame.Play(AI.SearchMove);
}
/// <summary>
/// calculate direct score by rules
/// </summary>
/// <param name="x">current board</param>
/// <returns>direct score</returns>
public static double DirectScore(Board x)
{
return(BoardControl.ScoreHelper(x, scoreTable) +
BoardControl.ScoreHelper(BoardControl.Transpose(x), scoreTable));
}