# Battleship: List Index Out of Range

#1

I have the if statement to print the message if you go over the index limit (i.e. out of the ocean) but whenever I try to test it with numbers that go off the grid I get an error instead of the "Oops, that's not even in the ocean." text.
Traceback (most recent call last):
File "python", line 34, in
IndexError: list index out of range

``````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)
guess_row = int(raw_input("Guess Row:"))
guess_col = int(raw_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:
print "You missed my battleship!"
board[guess_row][guess_col] = 'X'
print_board(board)

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)``````

#2

The order in which we run the conditional tests can be made to work to our advantage by testing the range before declaring a miss (and potentially raising index out range error, as in this case

``````elif guess_row not in range(5) or guess_col not in range(5):
# code
elif board[guess_row][guess_col] == 'X':
# code
else:
print "You missed my battleship!"
# code``````