Notebook

Day 1 - Another year, another first day¶

https://adventofcode.com/2019/day/1

As always, a warm-up excersice to start with. For me, it's the time of finding my aoc repository and upgrading all my packages first. :-)

In [1]:

import aocd

data = aocd.get_data(day=1, year=2019)
modules = list(map(int, data.splitlines()))

In [2]:

def fuel_requirement(mass: int) -> int:
    return mass // 3 - 2


tests = {
    12: 2,
    14: 2,
    1969: 654,
    100756: 33583,
}
for mass, expected in tests.items():
    assert (
        fuel_requirement(mass) == expected
    ), f"fuel_requirement({mass}) = {fuel_requirement(mass)} vs. {expected}"

In [3]:

print("Part 1:", sum(map(fuel_requirement, modules)))

Part 1: 3346639

Part two adds a little iteration; make sure to add to the total only if the new requirement is larger than 0!

In [4]:

def iterative_fuel_calc(mass: int) -> int:
    total = 0
    requirement = fuel_requirement(mass)
    while requirement > 0:
        total += requirement
        requirement = fuel_requirement(requirement)
    return total


tests = {
    14: 2,
    1969: 966,
    100756: 50346,
}
for mass, expected in tests.items():
    assert (
        iterative_fuel_calc(mass) == expected
    ), f"iterative_fuel_calc({mass}) = {iterative_fuel_calc(mass)} vs. {expected}"

In [5]:

print("Part 2:", sum(map(iterative_fuel_calc, modules)))

Part 2: 5017110