Sean McLemon | Advent of Code

2019-12-01 - The Tyranny of the Rocket Equation

(original .ipynb)

Day 1 puzzle input is a list of integers which represent weight of some modules on a spacecraft (mine is here). Part 1 involves applying a calculation to the weight to determine how much fuel is required, and summing up all fuel requirements Part 2 is an adjusted version of this calculation to take on board the fact that fuel adds weight that needs to be carried.

from math import floor

def required_fuel(mass):
    return (floor(mass/3.0)) - 2

assert 2 == required_fuel(12)
assert 2 == required_fuel(14)
assert 654 == required_fuel(1969)
assert 33583 == required_fuel(100756)

module_weights_lines = open("puzzle_input/day1.txt", "r").readlines()
module_weights = [int(mw) for mw in module_weights_lines]

module_fuel_required = [ required_fuel(module) for module in module_weights ]

print(sum(module_fuel_required))

3305301

def fully_loaded_fuel(module):
    total_fuel_required = required_fuel(module)
    additional_fuel = required_fuel(total_fuel_required)
    
    while additional_fuel > 0:
        total_fuel_required += additional_fuel
        additional_fuel = required_fuel(additional_fuel)
        
    return total_fuel_required

assert 2 == fully_loaded_fuel(14)
assert 966 == fully_loaded_fuel(1969)
assert 50346 == fully_loaded_fuel(100756)


fully_loaded_module_fuel_required = [ fully_loaded_fuel(module) for module in module_weights ]

print(sum(fully_loaded_module_fuel_required))

4955106