minimax fully implemented

1 files changed, 22 insertions, 17 deletions

diff --git a/ttt.c b/ttt.c
index c6f63e4..59181c1 100644
--- a/ttt.c
+++ b/ttt.c
@@ -118,28 +118,31 @@ struct PosInfo {
 };
 struct PosInfo minimax(int boardState[3][3], int turn) {
 	int eval;
-	int* bestMove = calloc(2, sizeof(int));
+	int bestMove[2] = { -1, -1 }; 
 	int s = get_game_state(boardState);
-	if(s == turn + 1) {
+	if(s == 1) {
 		eval = 10;
 	}
-	else if(s == (!turn) + 1) {
+	else if(s == 2) {
 		eval = -10;
 	}
-	else if(s == 4) {
+	else if(s == 3) {
 		eval = 0;
 	}
 	else {
-		int eval = 0;
-		for(int r = 0; r < 2; r++) {
-			for(int c = 0; c < 2; c++) {
-				int[3][3] simBoard;
-				memcpy(simBoard, boardState, sizeof(boardState));
-				if(simBoard[c][r] == 0) {
+		eval = -999;
+		for(int r = 0; r < 3; r++) {
+			for(int c = 0; c < 3; c++) {
+				if(boardState[c][r] == 0) {
+					int simBoard[3][3];
+					//deep copy boardState to simBoard
+					for(int i = 0; i < 9; i++) {
+						simBoard[i % 3][i / 3] = boardState[i % 3][i / 3];
+					} 
 					simBoard[c][r] = turn + 1;
-					struct PosInfo i = minimax(simBoard, !turn);
-					if(i.eval > eval) {
-						eval = i.eval;
+					struct PosInfo mr = minimax(simBoard, !turn);
+					if((turn == 0 && mr.eval > eval) || (turn == 1 && mr.eval < eval) || eval == -999) {
+						eval = mr.eval;
 						bestMove[0] = c;
 						bestMove[1] = r;
 					}
@@ -155,10 +158,12 @@ struct PosInfo minimax(int boardState[3][3], int turn) {
 }
 int* ai_input_pos(int boardState[3][3], int turn) {
 	struct PosInfo i = minimax(boardState, turn);
-	return i.pos;
+	int* nPos = malloc(2 * sizeof(int));
+	nPos[0] = i.pos[0];
+	nPos[1] = i.pos[1];
+	return nPos;
 }
-void clear_screen()
-{
+void clear_screen() {
     system("@cls||clear");
 }
 int main() {
@@ -169,7 +174,7 @@ int main() {
 		clear_screen();
 		draw_board(board);
 		int* tl = get_move_ptrs[turn](board, turn);
-		board[tl[0] - 1][3 - tl[1]] = turn + 1;
+		board[tl[0]][tl[1]] = turn + 1;
 		free(tl);
 		int s = get_game_state(board);
 		if(s == 1 || s == 2) {