Merge branch 'master' of https://github.tamu.edu/brj2013/Breakthrough

Engine.cpp

@@ -10,6 +10,8 @@
 Engine::Engine(){
 	Board* brd = new Board();
 	b = brd;
+	alpha = INT_MIN;
+	beta = INT_MAX;
 }
 
 void Engine::startGame(){
@@ -21,19 +23,23 @@ void Engine::startGame(){
 
 	int choice = -1;
 	cin >> choice;
+	cout<<"Enter AI difficulty: \n";
+	int difficulty;
+	cin >> difficulty;
+	
 	cout << "OK" << endl;
 
 	if (choice == 1)
-		userGame();
+		userGame(difficulty);
 	else if (choice == 2)
-		AIGame();
+		AIGame(difficulty);
 	else {
 		cout << "Please enter a valid choice.\n";
 		startGame();
 	}
 }
 
-void Engine::userGame(){
+void Engine::userGame(int difficulty){
 	string move;
 
 	bool gameOver = false; 
@@ -58,40 +64,43 @@ void Engine::userGame(){
 		}
 		
 		while(b->getTurn() == 'X' ){
-			//easyAI();
-			AI(3);
+			AI(difficulty);
 		}
 		
 		gameOver = b->isGameOver();
 		b->setValidFalse();
-		
 		b->snapshot(record, *b);
 	}
+	
 	b->displayBoard();
 	string s = "";
 	s += b->getTurn();
 	cout << "Game over. " + s + " wins!\n\n";
 }
 
-void Engine::AIGame(){
+void Engine::AIGame(int difficulty){
 	bool gameOver = false;
 
 	while (gameOver != true){
 		gameOver = b->isGameOver();
 		
 		while(b->getTurn() == 'O'){
-			AI(3);
+			AI(difficulty);
 		}
 		
 		b->displayBoard();
 		sleep(1);
 		
 		while(b->getTurn() == 'X' ){
-			AI(3);
+			AI(difficulty);
 		}
 		
 		gameOver = b->isGameOver();
 	}
+	
+	string s = "";
+	s += b->getTurn();
+	cout << "Game over. " + s + " wins!\n\n";
 }
 
 void Engine::AI(int depth){
@@ -111,42 +120,76 @@ void Engine::AI(int depth){
 void Engine::createMMTree(MNode* node, int depth, int alt){
 	MNode* temp;
 	char max, min;
+	bool cond = true;
 	Board current = node->getState();
 	vector<moves> listOfMoves = current.viewPossibleMoves();
 	
+	if (node->getType() == "max"){
+		if (node->getMMVal() <= alpha){
+			cond = false;
+		}
+	}
+	
+	else if (node->getType() == "min"){
+		if (node->getMMVal() >= beta){
+			cond = false;
+		}
+	}
+	
 	if (depth >= 0){
 		for (int i = 0; i < listOfMoves.size(); ++i){
 			if(current.getPiece(8 - listOfMoves[i].row, listOfMoves[i].column)->getType() == 
 								current.getTurn() && current.isThisMovePossible(8 - listOfMoves[i].row, 
 																				listOfMoves[i].column, 
 																				listOfMoves[i].moveType)){
-				current.resetTaken();
-				current = current.move(listOfMoves[i]);
-				max = current.getTurn();
-				current.changeTurns();
-				min = current.getTurn();
-				/*
-				if (current.checkTaken('X'))
-					cout << "xtaken true\n";
-				if (current.checkTaken('O'))
-					cout << "otaken true\n";
-				*/
-				temp = new MNode(current, listOfMoves[i], current.evaluate(max, min));
-				
-				if (alt == 1)
-					temp->setType("max");
-				else if (alt == 1)
-					temp->setType("min");
-				
-				current.resetTaken();
-				node->addChild(temp);
-				
-				createMMTree(temp, --depth, alt * -1);
-				
-				current.changeTurns();
+				if (cond){
+					current.resetTaken();
+					current = current.move(listOfMoves[i]);
+					max = current.getTurn();
+					current.changeTurns();
+					min = current.getTurn();
+					
+					/*
+					if (current.checkTaken('X'))
+						cout << "xtaken true\n";
+					if (current.checkTaken('O'))
+						cout << "otaken true\n";
+					*/
+					
+					temp = new MNode(current, listOfMoves[i], current.evaluate(max, min));
+					
+					if (alt == 1)
+						temp->setType("max");
+					else if (alt == 1)
+						temp->setType("min");
+					
+					current.resetTaken();
+					node->addChild(temp);
+					
+					createMMTree(temp, --depth, alt * -1);
+					
+					current.changeTurns();
+				}
 			}
 		}
 	}
+	
+	else {
+		if (node->getType() == "max"){
+			if (node->getMMVal() > alpha){
+				alpha = node->getMMVal();
+			}
+		}
+		
+		else if (node->getType() == "min"){
+			if (node->getMMVal() < beta){
+				beta = node->getMMVal();
+			}
+		}
+	}
+	
+	//cout << "alpha: " << alpha << "\n";
+	//cout << "beta: " << beta << "\n";
 
 	return;
 }
@@ -171,16 +214,14 @@ moves Engine::evaluateMMTree(MNode* node){
 }
 
 int Engine::evaluateMMBranch(MNode* node, int max){
-	if (node->getMMVal() > max)
-		max = node->getMMVal();
-
 	vector<MNode*> children = node->getChildren();
 	
 	for (auto &c : children){
 		evaluateMMBranch(c, max);
 	}
-
-	//cout << "max: " << max << "\n";
+	
+	if (node->getMMVal() > max)
+		max = node->getMMVal();
 	
 	return max;
 }

Engine.h

@@ -7,14 +7,14 @@ using namespace std;
 
 class Engine {
 	Board* b;
-	
+	int alpha, beta;
 	
 public:
 	Engine();
 	Board* getBoard() { return b; }
 	void startGame();
-	void userGame();
-	void AIGame();
+	void userGame(int difficulty);
+	void AIGame(int difficulty);
 	void AI(int depth);
 	void createMMTree(MNode* node, int depth, int alt);
 	moves evaluateMMTree(MNode* node);

README.md

@@ -1,5 +1,5 @@
 # Breakthrough
-Reposity for the second CSCE 315 project
+Repository for the second CSCE 315 project
 
 # To compile everything:
   make