2 dimentional list


#1

<PLEASE USE THE FOLLOWING TEMPLATE TO HELP YOU CREATE A GREAT POST!>

<Below this line, add a link to the EXACT exercise that you are stuck at.>

https://www.codecademy.com/courses/learn-python/lessons/battleship/exercises/danger-will-robinson?action=lesson_resume

<In what way does your code behave incorrectly? Include ALL error messages.>

There is no problem with code.

But the 2 dimentional list concept suddenly appears. In my code the board list is just a normal list. It appears in Row and Collum because the following code

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

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

print_board(board)

make it look so, and that is we see it to be 2 dimensional. There is no specific command that turn it into a 2 dimentional code

here is how it look

O O O O O
O O O O O
O O O O O
O O O O O
O O O O O

My question is: when does the board list become a 2 dimentional list?
<What do you expect to happen instead?>

```python
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(raw_input("Guess Row: "))
guess_col = int(raw_input("Guess Col: "))

# Write your code below!
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)

<do not remove the three backticks above>

#2

When it becomes a list of lists.

board.append(["O"] * 5)

["O"] * 5 is a list. We just appended it to a list.

It becomes a three dimensional list when those lists are also lists of lists. And so on.

It is not a true matrix, though, in the strictest sense. Lists are linear, no matter how you flesh them out.


#3

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