[JAVA] Need help trying to create an Artificial Intelligence in which the comput

Question

[JAVA] Need help trying to create an Artificial Intelligence in which the computer can never lose to the user in a game of Tic-Tac-Toe. I'm not sure how to come up with the algorithm. Any help would be appreciated. Here is an example of what the output of the program should be:

Sample input/output run 1**** Welcome to Tic Tac Toe This is the board: 1 2 3 4 5 6 7 8 9 Please make a move LILI I the probability of a win is:0.41 the probability of a draw is:0.20 the probability of a loss is:0.37 Please make a move IXIXIol lol I LI_l_l the probability of a win is:0.23 the probability of a draw is:0.25 the probability of a loss is:0.51 Please make a move XX 0 the probability of a win is 0.0 the probability of a draw is:0.0 the probability of a loss is:1.0 The winner is :0

Explanation / Answer

You can use the MInMax algorithm to acheive what you wanted.
Here is the example code for you :
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.Scanner;
class Point {
int x, y;
public Point(int x, int y) {
this.x = x;
this.y = y;
}
@Override
public String toString() {
return "[" + x + ", " + y + "]";
}
}
class PointAndScore {
int score;
Point point;
PointAndScore(int score, Point point) {
this.score = score;
this.point = point;
}
}
class Board {

List<Point> availablePoints;
Scanner scan = new Scanner(System.in);
int[][] board = new int[3][3];
public Board() {
}
public boolean isGameOver() {
//Game is over is someone has won, or board is full (draw)
return (hasXWon() || hasOWon() || getAvailableStates().isEmpty());
}
public boolean hasXWon() {
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == 1) || (board[0][2] == board[1][1] && board[0][2] == board[2][0] && board[0][2] == 1)) {
//System.out.println("X Diagonal Win");
return true;
}
for (int i = 0; i < 3; ++i) {
if (((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 1)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 1))) {
// System.out.println("X Row or Column win");
return true;
}
}
return false;
}
public boolean hasOWon() {
if ((board[0][0] == board[1][1] && board[0][0] == board[2][2] && board[0][0] == 2) || (board[0][2] == board[1][1] && board[0][2] == board[2][0] && board[0][2] == 2)) {
// System.out.println("O Diagonal Win");
return true;
}
for (int i = 0; i < 3; ++i) {
if ((board[i][0] == board[i][1] && board[i][0] == board[i][2] && board[i][0] == 2)
|| (board[0][i] == board[1][i] && board[0][i] == board[2][i] && board[0][i] == 2)) {
// System.out.println("O Row or Column win");
return true;
}
}
return false;
}
public List<Point> getAvailableStates() {
availablePoints = new ArrayList<>();
for (int i = 0; i < 3; ++i) {
for (int j = 0; j < 3; ++j) {
if (board[i][j] == 0) {
availablePoints.add(new Point(i, j));
}
}
}
return availablePoints;
}
public void placeAMove(Point point, int player) {
board[point.x][point.y] = player; //player = 1 for X, 2 for O
}
  
void takeHumanInput() {
System.out.println("Your move: ");
int x = scan.nextInt();
int y = scan.nextInt();
Point point = new Point(x, y);
placeAMove(point, 2);
}
public void displayBoard() {
System.out.println();
for (int i = 0; i < 3; ++i) {
for (int j = 0; j < 3; ++j) {
System.out.print(board[i][j] + " ");
}
System.out.println();
}
}
  
Point computersMove;
  
public int minimax(int depth, int turn) {
if (hasXWon()) return +1;
if (hasOWon()) return -1;
List<Point> pointsAvailable = getAvailableStates();
if (pointsAvailable.isEmpty()) return 0;

int min = Integer.MAX_VALUE, max = Integer.MIN_VALUE;

for (int i = 0; i < pointsAvailable.size(); ++i) {
Point point = pointsAvailable.get(i);   
if (turn == 1) {
placeAMove(point, 1);
int currentScore = minimax(depth + 1, 2);
max = Math.max(currentScore, max);
  
if(depth == 0)System.out.println("Score for position "+(i+1)+" = "+currentScore);
if(currentScore >= 0){ if(depth == 0) computersMove = point;}
if(currentScore == 1){board[point.x][point.y] = 0; break;}
if(i == pointsAvailable.size()-1 && max < 0){if(depth == 0)computersMove = point;}
} else if (turn == 2) {
placeAMove(point, 2);
int currentScore = minimax(depth + 1, 1);
min = Math.min(currentScore, min);
if(min == -1){board[point.x][point.y] = 0; break;}
}
board[point.x][point.y] = 0; //Reset this point
}
return turn == 1?max:min;
}
}
public class TicTacToe {
public static void main(String[] args) {
Board b = new Board();
Random rand = new Random();
  
b.displayBoard();
System.out.println("Select turn: 1. Computer 2. User: ");
int choice = b.scan.nextInt();
if(choice == 1){
Point p = new Point(rand.nextInt(3), rand.nextInt(3));
b.placeAMove(p, 1);
b.displayBoard();
}
  
while (!b.isGameOver()) {
System.out.println("Your move: ");
Point userMove = new Point(b.scan.nextInt(), b.scan.nextInt());
b.placeAMove(userMove, 2); //2 for O and O is the user
b.displayBoard();
if (b.isGameOver()) break;
  
b.minimax(0, 1);
  
b.placeAMove(b.computersMove, 1);
b.displayBoard();
}
if (b.hasXWon())
System.out.println("Unfortunately, you lost!");
else if (b.hasOWon())
System.out.println("You win!"); //Can't happen
else
System.out.println("It's a draw!");
}
}

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