Prologue
Advent of Code 2019 is an annual competition, in the vein of advent calendars, in which every day a new code challenge is unlocked. This year I’ll be taking AoC as an excuse to learn the basics of two new programming languages – Rust and Julia. Both have been seeing increasing usage in bioinformatics-land and I’ve been meaning to get my feet wet with them.
AoC is a great opportunity to do this since the challenges start small and build their way up. With the first few usually needing only the very basics of a language - conditional logic, IO, basic math and string operations.
As a baseline, I plan on producing answers in Python3 since I do most of my day-to-day data munging and programming with it. Hopefully the Python code is acceptable “fine” in terms of style and bigO… I am making no such promises about the Rust and Julia solutions. I’ll try and do as much as possible without the use of modules. It’s way more fun that way!
Python
nums = []
with open('Day1.input', 'r') as fh:
[nums.append(int(int(l.rstrip())/3.) - 2) for l in fh]
total = sum(nums)
print(f"You need {total} units of fuel, without accounting for fuel mass")
for n in nums:
while (n/3) > 2:
n = int(n/3.) - 2
total += n
print(f"You need {total} units of fuel, accounting for fuel mass")
You need 3311492 units of fuel, without accounting for fuel mass
You need 4964376 units of fuel, accounting for fuel mass
Julia
total = 0
nums = Vector{Int}()
open("Day1.input") do fh
for l in eachline(fh)
push!(nums, div(parse(Int,l), 3) - 2)
end
end
tot = sum(nums)
println("You need $tot units of fuel, without accounting for fuel mass")
for n in nums
while div(n, 3) > 2
n = div(n, 3) - 2
global tot += n
end
end
println("You need $tot units of fuel, accounting for fuel mass")
Rust
Coming soon ™