public static List<Node> GenerateSuccessors(Board board, bool isBlack)
{
//Validate moves based on current state to generate new states
var nodes = new List<Node>();
//Generate # of valid moves
var ValidMoves = GetNumberOfMoves(board);
//Foreach valid move, generate a new node (evaluated in minimax)
for (var i = 0; i < ValidMoves.Length; i++)
{
if (ValidMoves[i])
{
var tempBoard = new Board(board.State);
//Make the move
tempBoard.AddToBoard(i, isBlack);
//Create a Node
var node = new Node();
node.Board = tempBoard;
nodes.Add(node);
}
}
return nodes;
}
//This method will search all the columns and return the best move for the AI to make.
//Will run AlphaBeta or regular Minimax depending on user selection.
public static int AiHelperMove(Board board, bool alphabeta, int depth)
{
var rows = board.State.GetLength(1) - 1;
int bestValue = Int32.MinValue;
int bestColumn = -1;
if (alphabeta)
{
MiniMaxAb miniMaxAb = new MiniMaxAb();
for (var i = 0; i <= rows; i++)
{
var node = new Node();
var tempBoard = new Board(board.State);
if (tempBoard.ValidateMove(i))
{
tempBoard.AddToBoard(i, true);
node.Board = tempBoard;
var currentValue = miniMaxAb.Search(node, depth, Int32.MinValue, Int32.MaxValue, false);
if (currentValue >= bestValue)
{
bestValue = currentValue;
bestColumn = i;
}
}
}
}
else
{
MiniMax miniMax = new MiniMax();
for (var i = 0; i <= rows; i++)
{
var node = new Node();
var tempBoard = new Board(board.State);
if (tempBoard.ValidateMove(i))
{
tempBoard.AddToBoard(i, true);
node.Board = tempBoard;
var currentValue = miniMax.Search(node, depth, false);
if (currentValue >= bestValue)
{
bestValue = currentValue;
bestColumn = i;
}
}
}
}
return bestColumn;
}
public static bool[] GetNumberOfMoves(Board board)
{// Check if each column is full
var col = board.State.GetLength(1);
var validColumnsToMoveTo = new bool[col];
//Initialize boolean array, each cell represents a column
for (var i = 0; i < validColumnsToMoveTo.Length; i++)
{
validColumnsToMoveTo[i] = false;
}
for (var i = 0; i < col; i++)
{
if (board.State[0, i] == null)
{
validColumnsToMoveTo[i] = true;
}
}
return validColumnsToMoveTo;
}
//Returns all adjacent pieces to a given piece, hardcoded the search, could have been better.
public static List<Tuple<bool, Piece>> GetAdjacentPieces(Piece piece, Board board)
{
var row = board.State.GetLength(0) - 1;
var col = board.State.GetLength(1) - 1;
var listOfAdjacentPieces = new List<Tuple<bool, Piece>>();
if (piece.Position.Row > 0) //Top Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(false, board.State[piece.Position.Row - 1, piece.Position.Col]));
}
if (piece.Position.Col < col && piece.Position.Row > 0) //TopRight Boundary Test
{
var adjPiece = board.State[piece.Position.Row - 1, piece.Position.Col + 1];
listOfAdjacentPieces.Add(Tuple.Create(true, adjPiece));
}
if (piece.Position.Col < col) //Right Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(false, board.State[piece.Position.Row, piece.Position.Col + 1]));
}
if (piece.Position.Row < row && piece.Position.Col < col) //BottomRight Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(true, board.State[piece.Position.Row + 1, piece.Position.Col + 1]));
}
if (piece.Position.Row < row)//Bottom Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(false, board.State[piece.Position.Row + 1, piece.Position.Col]));
}
if (piece.Position.Row < row && piece.Position.Col > 0) //BottomLeft Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(true, board.State[piece.Position.Row + 1, piece.Position.Col - 1]));
}
if (piece.Position.Col > 0) //Left Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(false, board.State[piece.Position.Row, piece.Position.Col - 1]));
}
if (piece.Position.Row > 0 && piece.Position.Col > 0)//TopLeft Boundary Test
{
listOfAdjacentPieces.Add(Tuple.Create(true, board.State[piece.Position.Row - 1, piece.Position.Col - 1]));
}
return listOfAdjacentPieces;
}
static void Main(string[] args)
{
//Following is setup for AI and board
Console.WriteLine("Welcome to Simacogo! You are Player 1, Color white.");
Console.WriteLine("At any time, type 'exit' to leave the game!");
Console.WriteLine("----------------------------------------------------------");
Console.WriteLine("\n");
Console.WriteLine("Enter # of plies for AI to search to? (numeric only)");
var depth = Int32.Parse(Console.ReadLine()); //AI lookahead value
Console.WriteLine("\n");
Console.WriteLine("Enable Alpha Beta Pruning? (True or False)");
var alphabeta = Boolean.Parse(Console.ReadLine()); //AI lookahead value
Console.WriteLine("\n");
Console.WriteLine("Enter board width? (numeric only)");
var width = Int32.Parse(Console.ReadLine()); //Board width
Console.WriteLine("Enter board height? (numeric only)");
var height = Int32.Parse(Console.ReadLine()); //Board height
Console.WriteLine("\n");
Board board = new Board(width, height);
bool humanTurn = true;
bool runProgram = true;
while (!board.IsFull() && runProgram)
{
if (humanTurn)
{
Console.WriteLine("--------------------Begin Human Turn-----------------------------------");
Console.WriteLine("Please type the column you want to drop a piece into and press enter. (1-9)");
string enteredValue = Console.ReadLine();
if (enteredValue.Equals("exit"))
{
runProgram = false;
break;
}
int colValue = Int32.MinValue;
Int32.TryParse(enteredValue, out colValue);
if (colValue > 0 && colValue < 10 && board.ValidateMove(colValue-1))
{
//Get column from User && Create new piece and enter it in the board at deepest possible position in column.
board.AddToBoard(colValue-1, false);
board.PrintState();
var node = new Node();
node.Board = board;
var score = Utility.FinalScore(node);
Console.WriteLine("\n");
Console.WriteLine("Current Score: \n");
Console.WriteLine("Human: " + score.Item1);
Console.WriteLine("AI " + score.Item2);
Console.WriteLine("--------------------End Human Turn----------------------");
Console.WriteLine("\n");
humanTurn = !humanTurn;
}
else
{
Console.WriteLine("Invalid selection, please try again.");
}
}
else
{
Console.WriteLine("--------------------Begin AI Turn--------------------");
//Let AI player pick position
//Update Board
//AI Runs either Miniax or MinimaxAB depending on user selection.
var bestMove = Utility.AiHelperMove(board, alphabeta, depth);
board.AddToBoard(bestMove, true);
board.PrintState();
var node = new Node();
node.Board = board;
var score = Utility.FinalScore(node);
Console.WriteLine("\n");
Console.WriteLine("Current Score: \n");
Console.WriteLine("Human: " + score.Item1);
Console.WriteLine("AI " + score.Item2);
Console.WriteLine("\n");
Console.WriteLine("--------------------End AI Turn----------------------");
humanTurn = !humanTurn;
}
}
Console.WriteLine("\n");
Console.WriteLine("Gameboard is Full!");
Console.WriteLine("\n");
var finalNode = new Node();
var tempBoard = new Board(board.State);
finalNode.Board = tempBoard;
var finalScore = Utility.FinalScore(finalNode);
Console.WriteLine("Final Board");
Console.WriteLine("\n");
board.PrintState();
Console.WriteLine("\n");
Console.WriteLine("Final Score Is: ");
Console.WriteLine("Human: " + finalScore.Item1);
Console.WriteLine("AI: " + finalScore.Item2);
Console.WriteLine("Thank you for playing Simacogo! Application will close in 5 seconds.");
System.Threading.Thread.Sleep(5000);
}
