Question

i’m learning python through the codeacademy website.
Now i;m trying to code the battleship project,where i face a problem:
my code is:

import random

board = []

for x in range(0,5):
  board.append(["O"] * 5)

def print_board(board):
  for row in board:
    print " ".join(row)

print_board(board)

def random_row(board):
  return random.randint(0,len(board)-1)

def random_col(board):
    return random.randint(0,len(board[0])-1)

ship_row = random_row(board)
ship_col = random_col(board)
guess_row = input("Guess Row:")
guess_col = input("Guess Col:")

print ship_row
print ship_col

if (guess_row == ship_row and guess_col == ship_col):
    print "Congratulations! You sank my battleship!"
else:
    if((guess_row < 0) or (guess_row > (len(board) -1) or (guess_col < 0) or (guess_col> (len(board) -1)):
        print "Oops, that’s not even in the ocean."
    else:
        print "You missed my battleship!"
        guess_row = "X"
        guess_col = "X"
        print_board(board)
    if board[guess_row][guess_col] == "X":
        print "You guessed that one already."

but it returns this error:

    if((guess_row < 0) or (guess_row > (len(board) -1) or (guess_col < 0) or (guess_col> (len(board) -1)):
                                                                                                         ^
SyntaxError: invalid syntax

Can you help me with this situation?

thank in advance guys

Answer 1

You have nine opening but only seven closing parentheses.

I personally would remove most of them:

 if guess_row < 0 or guess_row >= len(board) or guess_col < 0 or guess_col >= len(board):

or, better still:

 if not (0 <= guess_row < len(board)) or not (0 <= guess_col < len(board)):

Here, the two pairs of parentheses after not are not necessary, but IMO improve readability. Feel free to drop them if you disagree.

There are some other issues with the code.

The following:

    guess_row = "X"
    guess_col = "X"

should probably read

    board[guess_row][guess_col] = "X"

Also the if board[guess_row][guess_col] == "X": check should be done either before or instead of setting board[guess_row][guess_col] to "X" for the current guess_row and guess_col.