我正在尝试通过Jason Fox的最小最大算法(http://neverstopbuilding.com/minimax)进行实现,但它不起作用,电脑只是随机移动。下面是我编写的Game
类(我必须创建一个cloneGrid
函数,因为数组被传递为引用,有没有更好的方法来解决这个问题?):
class Game
{
public enum Piece { Empty = 0, X = 1, O = 2 };
static int[,] winConditions = new int[8, 3]
{
{ 0, 1, 2 }, { 3, 4, 5 }, { 6, 7, 8 },
{ 0, 3, 6 }, { 1, 4, 7 }, { 2, 5, 8 },
{ 0, 4, 8 }, { 2, 4, 6 }
};
public Piece[] Grid = new Piece[9];
public Piece CurrentTurn = Piece.X;
int Choice = 0;
public Piece Computer;
public Piece Player;
public Game()
{
CurrentTurn = Piece.X;
Player = Piece.X;
}
public void Reset()
{
CurrentTurn = Piece.X;
SetPlayer(Piece.X);
Grid = new Piece[9];
}
public void SetPlayer(Piece Player)
{
this.Player = Player;
this.Computer = switchPiece(Player);
}
public void MakeMove(int Move)
{
if(CurrentTurn == Player)
{
Grid = makeGridMove(Grid, CurrentTurn, Move);
CurrentTurn = switchPiece(CurrentTurn);
}
else if(CurrentTurn == Computer)
{
minimax(cloneGrid(Grid), CurrentTurn);
Grid = makeGridMove(Grid, CurrentTurn, Choice);
CurrentTurn = switchPiece(CurrentTurn);
Console.WriteLine(Choice.ToString());
}
}
int minimax(Piece[] InputGrid, Piece Player)
{
Piece[] Grid = cloneGrid(InputGrid);
if (checkScore(Grid, Player) != 0)
return checkScore(Grid, Player);
else if (checkGameEnd(Grid)) return 0;
List<int> scores = new List<int>();
List<int> moves = new List<int>();
for (int i = 0; i < 9; i++)
{
if (Grid[i] == Piece.Empty)
{
scores.Add(minimax(makeGridMove(Grid, Player, i), switchPiece(Player)));
moves.Add(i);
}
}
if(Player == Computer)
{
int MaxScoreIndex = scores.IndexOf(scores.Max());
Choice = moves[MaxScoreIndex];
return scores.Max();
}
else
{
int MinScoreIndex = scores.IndexOf(scores.Min());
Choice = moves[MinScoreIndex];
return scores.Min();
}
}
static int checkScore(Piece[] Grid, Piece Player)
{
if (checkGameWin(Grid, Player)) return 10;
else if (checkGameWin(Grid, switchPiece(Player))) return -10;
else return 0;
}
static bool checkGameWin(Piece[] Grid, Piece Player)
{
for(int i = 0; i < 8; i++)
{
if
(
Grid[winConditions[i, 0]] == Player &&
Grid[winConditions[i, 1]] == Player &&
Grid[winConditions[i, 2]] == Player
)
{
return true;
}
}
return false;
}
static bool checkGameEnd(Piece[] Grid)
{
foreach (Piece p in Grid) if (p == Piece.Empty) return false;
return true;
}
static Piece switchPiece(Piece Piece)
{
if (Piece == Piece.X) return Piece.O;
else return Piece.X;
}
static Piece[] cloneGrid(Piece[] Grid)
{
Piece[] Clone = new Piece[9];
for (int i = 0; i < 9; i++) Clone[i] = Grid[i];
return Clone;
}
static Piece[] makeGridMove(Piece[] Grid, Piece Move, int Position)
{
Piece[] newGrid = cloneGrid(Grid);
newGrid[Position] = Move;
return newGrid;
}
}