Tic-Tac-Toe

A two-player, console-based Tic-Tac-Toe game written in C++ as a Semester 1 project. Two people share one keyboard, take turns choosing board positions, and the program tracks wins and draws across as many rounds as they want to play.

Features

• Local two-player game with custom player names
• Player 1 plays as X and Player 2 plays as O; Player 1 moves first in every round
• Numbered board (positions 1-9) redrawn after every move
• Win detection across all rows, columns, and both diagonals
• Draw detection when all nine moves are used without a winner
• Input validation for non-numeric input, out-of-range numbers, and already-taken positions
• Scoreboard (wins per player and draws) shown after each round and again when the game ends
• Play-again loop so multiple rounds can be played in a single session

Tech Stack

Category	Details
Language	C++
Standard library	<iostream>, <string>, <limits>
Compiler	Any C++ compiler such as g++ (MinGW on Windows)

The program has no external dependencies.

Project Structure

tic-tac-toe/
|-- main.cpp     # Complete game logic in a single source file
|-- LICENSE      # MIT License
`-- README.md

How It Works

All logic lives in main.cpp:

Function	Purpose
resetBoard()	Fills the 3x3 board with the characters '1' to '9' at the start of each round
showBoard()	Clears the screen and prints the title, both player names, and the current board
hasWon()	Checks the three rows, three columns, and two diagonals for three matching cells
playRound()	Runs one round and returns 1 (Player 1 wins), 2 (Player 2 wins), or 0 (draw)
main()	Reads player names, loops over rounds, updates the scoreboard, and asks whether to play again

The board is stored in a global char board[3][3]. An unplayed cell holds its position number, and a played cell holds 'X' or 'O'. A move is rejected if the chosen cell already contains 'X' or 'O'.

Board positions map to the grid as follows:

 1 | 2 | 3
---|---|---
 4 | 5 | 6
---|---|---
 7 | 8 | 9

Prerequisites

• A C++ compiler such as g++ (for example, MinGW on Windows)
• A Windows terminal, because the program calls system("cls") to clear the screen

Getting Started

Clone the repository and move into it:

git clone https://github.com/stackiid/tic-tac-toe.git
cd tic-tac-toe

Compile the game:

g++ main.cpp -o tictactoe

Run it:

# Windows PowerShell
.\tictactoe.exe

# Windows Command Prompt
tictactoe

Usage

1. Start the program and enter a name for Player 1 and Player 2.
2. Press Enter to begin. Player 1 plays as X and Player 2 plays as O.
3. On your turn, type a position number from 1 to 9 and press Enter.
4. The round ends when a player completes a line or all nine cells are filled.
5. After each round the scoreboard is displayed. Enter y or Y to play another round; any other character ends the game and shows the final result.

Example of a board in progress:

  +------  TIC-TAC-TOE  ------+
    Alice [X]   vs   Bob [O]

       X | 2 | 3
      ---|---|---
       4 | O | 6
      ---|---|---
       7 | 8 | 9

  Alice [X]  >>  Choose a position (1-9):

Input Handling

Situation	Behavior
Non-numeric input	Input is discarded, a "Numbers only" message is shown, and the same player is prompted again after pressing Enter
Number outside 1-9	A "taken or out of range" message is shown and the same player is prompted again after pressing Enter
Position already taken	Same message as above; the turn is not consumed

Platform Notes

• Screen clearing uses system("cls"), which works on Windows only. On Linux or macOS the game still compiles, but the screen is not cleared properly. Replacing "cls" with "clear" in main.cpp (it appears in showBoard() and main()) is the straightforward fix for those systems.
• There is no AI opponent; the game is strictly for two human players.
• There are no automated tests in the repository.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Copyright (c) 2026 Ubaid Ahmad