Question

Write a program that plays tic-tac-toe. The tic-tac-toe game is played on a 3 × 3 grid as shown below:

The game is played by two players, who take turns. The first player marks moves with a circle, the second with a cross. The player who has formed a horizontal, vertical, or diagonal sequence of three marks wins. Your program should draw the game board, ask the user for the coordinates of the next mark (their move), change the players after every successful move, and pronounce the winner.

This is the the code so far:

public static void main(String[] args) {
       Scanner in = new Scanner(System.in);
       int[][] board = new int[3][3];
      

   }

Answer 1

So, here is the solution of the given problem.
I am attaching the well-commented source code along with the Screenshots of the code as well as output.

Source Code:

import java.util.Scanner;

public class Main
{
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int[][] board = new int[3][3];
        int x,y;
        boolean flag = true;

        //function to print instruction
        printInstruction();

        //run game infinitely till one player won or game ties
        while (true){
            //function to print board
            print(board);

            //to print player whose chance is there
            System.out.println("Player" + ((flag)?"1":"2"));

            //taking co-ordinated
            x = in.nextInt();
            y = in.nextInt();

            //checking if is vacant or not
            if (board[x-1][y-1] == 0){
                board[x-1][y-1] = ((flag)? 1 : 2 );
                flag = !flag;
            }
            else
                System.out.println("Invalid Move!");

            //check if player won or not
            if(check(board)){
                System.out.println("Player " + ((flag)?"2":"1") + " won.");
                break;
            }
            //to check if game ties or not
            if(completeFill(board)) {
                System.out.println("Game Tie");
                break;
            }
        }

    }
//to check board is completely filled and no player won
    private static boolean completeFill(int[][] board){
        for(int i = 0;i<3;i++){
            for(int j = 0;j<3;j++){
                if(board[i][j] != 0)
                    return false;
            }
        }
        return true;
    }
//to print instructions
    private static void printInstruction() {
        System.out.println("1. You have to enter row number (1-3) and column number (1-3) to place your element: ");
        System.out.println("2. Game will start from player 1 and one by one each player's turn will come.");
    }


    //function to check row is matched
    private static boolean rowCrossed(int[][] board)
    {
        for (int i=0; i<3; i++)
        {
            if (board[i][0] == board[i][1] &&
                    board[i][1] == board[i][2] &&
                    board[i][0] != 0)
                return true;
        }
        return false;
    }

    //function to check column is matched
   private static boolean columnCrossed(int[][] board)
    {
        for (int i=0; i<3; i++)
        {
            if (board[0][i] == board[1][i] &&
                    board[1][i] == board[2][i] &&
                    board[0][i] != 0)
                return true;
        }
        return false;
    }


    //function to check diagonal is matched
    private static boolean diagonalCrossed(int[][] board)
    {
        if (board[0][0] == board[1][1] &&
                board[1][1] == board[2][2] &&
                board[0][0] != 0)
            return true;

        return board[0][2] == board[1][1] &&
                board[1][1] == board[2][0] &&
                board[0][2] != 0;
    }

    //function to check if any of the condition is satisfied i.e row,column,diagonal
    private static boolean check(int[][] board){
            return rowCrossed(board) || columnCrossed(board) || diagonalCrossed(board);
    }

    //function to print board
    private static void print(int[][] board){
        for(int i = 0;i<3;i++) {
            for(int j = 0;j<3;j++)
                System.out.print(" | " + board[i][j]);
            System.out.println();
            if(i<2)
               System.out.println("--------------");
        }
    }
}

Screenshot of Source Code:

Output:

So, this was the solutions of the problem.
I hope I am able to solve your problem, if yes then do give it a like.
It really helps :)