tictactoe

Tic Tac Toe

This program implements a classic Tic Tac Toe game where you play against an AI opponent that uses the minimax algorithm to make optimal moves. The game runs in the console and features a smart computer player that's difficult to beat!

Compile

1. Save the code in a file named tictactoe.c
2. Compile with GCC:

   ./build
   

3. Run the executable:

   ./tictactoe

Game Features

• Player vs Computer: You play as 'X' and the computer plays as 'O'
• Smart AI: Computer uses the minimax algorithm to make optimal moves
• Win Detection: Automatically detects wins for either player
• Draw Detection: Recognizes when the game ends in a tie
• Input Validation: Checks for valid moves and occupied positions

Gameplay Instructions

1. The game board positions are numbered 1-9:

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

2. On your turn, enter a number (1-9) to place your 'X' in that position
3. The computer will automatically respond with its 'O' move
4. The game ends when either:
   • A player gets three in a row (horizontally, vertically, or diagonally)
   • The board is full (draw)

Key Functions

minimax(char grid[3][3], char player)

• Implements the minimax algorithm to evaluate board positions
• Returns a score representing the game state:
  • 10: Computer ('O') wins
  • -10: Player ('X') wins
  • 0: Draw or neutral position
• Recursively evaluates all possible moves to find the optimal play

findBestMove(char grid[3][3])

• Uses the minimax scores to determine the computer's best move
• Iterates through all empty positions
• Selects the move with the highest minimax score for the computer

check_win(char grid[3][3], char player)

• Checks all possible win conditions:
  • Horizontal rows
  • Vertical columns
  • Main diagonal
  • Anti-diagonal
• Returns 1 if the specified player has won, 0 otherwise

full_grid(char grid[3][3])

• Checks if the board is completely filled
• Returns 1 if full (draw), 0 otherwise

print(char grid[3][3])

• Displays the current game board in a user-friendly format
• Shows player moves and board boundaries