# 2. Python Program to Display a 3×3 Tic-Tac-Toe Board

### Program

```python
# Tic-Tac-Toe Board
# State Representation

board = [" " for _ in range(9)]

# Display the board
def display_board():
    print()
    print(board[0], "|", board[1], "|", board[2])
    print("--+---+--")
    print(board[3], "|", board[4], "|", board[5])
    print("--+---+--")
    print(board[6], "|", board[7], "|", board[8])
    print()

# Display initial board
print("Initial Tic-Tac-Toe Board:")
display_board()

# Get position from user
position = int(input("Enter a position (1-9) to place X: "))

# Place X on the selected position
if 1 <= position <= 9:
    board[position - 1] = "X"

# Display updated board
print("Updated Tic-Tac-Toe Board:")
display_board()
```

### Sample Output

```text
Initial Tic-Tac-Toe Board:

  |   |  
--+---+--
  |   |  
--+---+--
  |   |  

Enter a position (1-9) to place X: 5

Updated Tic-Tac-Toe Board:

  |   |  
--+---+--
  | X |  
--+---+--
  |   |  
```

### State Representation

The board is represented using a **list of 9 elements**:

```python
board = [" " for _ in range(9)]
```

The positions are mapped as:

```text
1 | 2 | 3
--+---+--
4 | 5 | 6
--+---+--
7 | 8 | 9
```

For example, if the user enters **5**, the state becomes:

```python
[" ", " ", " ", " ", "X", " ", " ", " ", " "]
```

This program **does not implement the complete game logic**; it only demonstrates the board state and placing an `X`.