public int MINIMAX_DECISION(Game game)
{
_stopwatch = new System.Diagnostics.Stopwatch();
_stopwatch.Start();
int maxValue = int.MinValue;
List<int> colOptions = new List<int>();
List<int> actions = ACTIONS(game);
int iterationCounter = 0;
foreach (int column in actions)
{
iterationCounter++;
int v = MIN_VALUE(RESULT(game, column, _max), 1);
if (v > maxValue)
{
maxValue = v;
colOptions.Clear();
colOptions.Add(column);
}
else if (v == maxValue)
{
colOptions.Add(column);
}
if (_stopwatch.Elapsed.Seconds > (game.TimeLimitSeconds - 1)) break;
}
int c = colOptions[_rnd.Next(colOptions.Count)];
Console.WriteLine("Column selection: {0} / Elapsed: {1} / Total Actions: {2} / Actions Evaluated: {3}", c, _stopwatch.Elapsed, actions.Count, iterationCounter);
return c;
}
public int MIN_VALUE(Game game, int depth)
{
if (TERMINAL_TEST(game, depth))
return UTILITY(game);
int value = int.MaxValue;
foreach (int column in ACTIONS(game))
{
value = Math.Min(value, MAX_VALUE(RESULT(game, column, _min), ++depth));
}
return value;
}
static void PlayGame(System.IO.StreamWriter writer)
{
Game g = new Game()
{
Rows = 6,
Columns = 7,
PiecesToWin = 4,
TimeLimitSeconds = 30
};
g.Initialize();
Player p1 = new MinimaxPlayer(Players.Black, Players.Red, "MINIMAX (1)");
p1.SetGameInfo(g.Rows, g.Columns, g.PiecesToWin, 0, g.TimeLimitSeconds);
Player p2 = new Player(Players.Red, Players.Black, "SIMPLE (2)");
p2.SetGameInfo(g.Rows, g.Columns, g.PiecesToWin, 1, g.TimeLimitSeconds);
GameValueCalculator calc = new GameValueCalculator(g);
GameResult result = GameResult.InProgress;
while (result == GameResult.InProgress)
{
int move = p1.GetNextMove();
g.AcceptMove(p1.ID, move);
result = calc.EvaluateGameState();
p2.NoteOpponentsMove(move);
if (result == GameResult.WinBlack || result == GameResult.WinRed) break;
move = p2.GetNextMove();
g.AcceptMove(p2.ID, move);
result = calc.EvaluateGameState();
p1.NoteOpponentsMove(move);
}
Console.WriteLine(string.Format(" --- {0} --- ", result));
g.DisplayBoard();
writer.WriteLine(string.Format(" --- {0} --- ", result));
g.DisplayBoard(writer);
}
static void DiagnoseFdUpMoves()
{
Game g = new Game()
{
Rows = 6,
Columns = 7,
PiecesToWin = 4,
TimeLimitSeconds = 30000
};
g.Initialize();
g.AcceptMove(Players.Black, 3);
g.AcceptMove(Players.Red, 4);
g.AcceptMove(Players.Black, 3);
g.AcceptMove(Players.Red, 3);
MinimaxCs.Minimax m = new MinimaxCs.Minimax(Players.Black);
int col = m.MINIMAX_DECISION(g);
}
public Game Clone()
{
Game clone = new Game()
{
Rows = this.Rows,
Columns = this.Columns,
PiecesToWin = this.PiecesToWin,
TimeLimitSeconds = this.TimeLimitSeconds
};
clone.Initialize();
for (int r = 0; r < this.Rows; r++)
{
for (int c = 0; c < this.Columns; c++)
{
clone.Board[r, c] = this.Board[r, c];
}
}
return clone;
}
int UTILITY(Game game)
{
GameValueCalculator calc = new GameValueCalculator(game);
return calc.CalculateValues(_max).NormalizedValue;
}
bool TERMINAL_TEST(Game game, int depth)
{
if (_stopwatch.Elapsed.Seconds > (game.TimeLimitSeconds - 2)) return true;
if (depth >= MAX_DEPTH) return true;
GameValueCalculator calc = new GameValueCalculator(game);
if (calc.IsGameComplete()) return true;
return false;
}
List<int> ACTIONS(Game game)
{
List<int> actions = new List<int>();
for (int c = 0; c < game.Columns; c++)
{
if (game.Board[0, c] == (int)Players.None)
actions.Add(c);
}
return actions;
}
public Game RESULT(Game game, int column, Players playerId)
{
Game newState = game.Clone();
newState.AcceptMove(playerId, column);
return newState;
}
public GameValueCalculator(Game game)
{
_game = game;
}