14. Test Run - Accounting for blank or non-int inputs


#1

Hi, all. What is the best way to account for any blank or non-int input (string, alphanumeric, etc.) for guess_row and guess_col?

This is the error message with any non-int input:

Traceback (most recent call last):
  File "python", line 22, in <module>
ValueError: invalid literal for int() with base 10: '1 1'

My current code:

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

# Write your code below!
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)

Any help would be greatly appreciated!


#2

Hi @arcwhiz60917 ,

This is line 22 ...

guess_row = int(raw_input("Guess Row:"))

The int built in function raises an error if you try to convert a value to an int, if that conversion cannot be performed. If you enter the string, "1 1", as input, it cannot be converted to an int.


#3

@geomaticmashups

Thank you so much for pointing this out. It makes perfect sense now!