The Shared Row

The function create_board(size) creates a square game board filled with zeros and places a 1 in the center cell. Only the center cell should be 1 — all other cells should be 0.

Instead, every row in the board gets the 1, not just the middle one. Changing one cell somehow changes all of them.

The board-creation line looks completely normal. What is * size actually doing to the rows?

# your fix

+ must use for

hint 2after hint 1

hint 3after hint 2

solution

Read the code. Before running anything: what does the last line below give?

def create_board(size):

"""

Creates a square game board of the given size, filled with zeros,

then places a 1 in the center cell. Returns the board.

Only the center cell should be 1 — all other cells should be 0.

Example: create_board(3) -> [[0, 0, 0], [0, 1, 0], [0, 0, 0]]

"""

board = [[0] * size] * size

mid = size // 2

board[mid][mid] = 1

return board

>>> create_board(3)