14. It randomly throws an error and I'm not sure why


#1
from random import randint

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 randint(0, len(board) - 1)

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

ship_row = random_row(board)
ship_col = random_col(board)
print(ship_row)
print(ship_col)

guess_row = int(input("Guess Row: "))
guess_col = int(input("Guess Col: "))

if guess_row == ship_row and \
   guess_col == ship_col:
  print("Congratulations! You sank my battleship!")
else:
  if guess_row not in range(5) or \
     guess_col not in range(5):
    print("Oops, that's not even in the ocean.")
  elif board[guess_row][guess_col] == "X":
    print("You guessed that one already.")
  else:
    print("You missed my battleship!")
    board[guess_row][guess_col] = "X"
    print_board(board)

error:

Traceback (most recent call last):
  File "python", line 25, in <module>
  File "<string>", line 1, in <module>
NameError: name 'RUN' is not defined

edit: I’ve figured out that it happens every other time and that the time after it throws an error, I can’t input anything.

edit 2: I’ve figured it out, I think. I’m not running the program all the way through every time, just hitting re-running it. For some reason, this doesn’t completely restart the program, just causes an error when I do it. If I go through the program completely, it doesn’t throw an error.


#2

Hi @courserockstar22708,

Make sure you run it through each time, entering numbers for the row and column, when prompted.

Why are you using input instead of raw_input here? …

guess_row = int(input("Guess Row: "))
guess_col = int(input("Guess Col: "))

Edited December 15, 2017 to add the following …

In general it is risky to use input in Python 2, which is the version that is running in the Codecademy exercises. The Python 2 interpreter attempts to evaluate what the user enters in response to input as a Python expression. Although that may not cause a problem when a number is entered, it can raise errors when the user enters text. With a Python 2 program that is running publicly on a server, input can also enable hackers to enter malicious code at a prompt or in a text area on a web page.

For the reasons provided above, it is best to raw_input with Python 2. In Python 3, input replaces raw_input.


#3

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