def calculate_additional_fuel(initial_fuel):
"""
Recursively calculate the amount of fuel required to carry the fuel.
Of course it could be done without the recursion
but I have decided to show off
:param initial_fuel: the amount of fuel needed to carry
:return: the amount of fuel needed for carrying the initial fuel tank
"""
additional_fuel = calculate_fuel(initial_fuel)
if additional_fuel <= 0:
return 0
else:
return additional_fuel + calculate_additional_fuel(additional_fuel)
def solution():
from pathlib import Path
input_file = Path(INPUT_FILE)
fuel_sum = 0
with open(input_file, 'r') as puzzle_input:
for line in puzzle_input:
payload_fuel = calculate_fuel(line)
fuel_for_fuel = calculate_additional_fuel(payload_fuel)
fuel_sum += (payload_fuel + fuel_for_fuel)
return fuel_sum
def test_2():
assert calculate_fuel(14) == 2
def test_1():
assert calculate_fuel(12) == 2
def test_4():
assert calculate_fuel(100756) == 50346
def test_3():
assert calculate_fuel(1969) == 966