### Task Start ###
# These are the assertions for your function:
assert count_ways(2) == 3

""" Write a function to find the number of ways to fill it with 2 x 1
dominoes for the given 3 x n board. """
def count_ways(n):

if n == 0:

return 1

if n == 1:

return 1

if n == 2:

return 3

return count_ways(n-1) + count_ways(n-2)

Here is a line-by-line explanation of the code:
‘def count_ways(n):‘: This line defines a function named ‘count_ways‘ that
takes a single argument, ‘n‘. ‘n‘ represents the width of the 3 x n board.

‘if n == 0:‘: This line checks if n is equal to 0. In other words, it checks
if the width of the board is 0. If the width of the board is 0, there is
only one way to fill it: by not placing any dominoes.

‘return 1‘: If the condition in line 2 is true (i.e., n is 0), the function
returns 1, indicating that there is only one way to fill the 3 x 0 board.
Teaching Large Language Models to Self-Debug