Advent of Code 2024.
Starting in Python to learn about the language.
I'll try and document my main learnings here as the days go by.
zip is very nice, exactly the kind of nice-to-have I expect from Python. It accepts any number of iterables, and returns a list of tuples with an element from each in order.
When dealing with dictionaries, found two different ways of setting default values if a key doesn't exist. First, using .get(key, default). Didn't like it here because it made this particular code too verbose without any need. Looking more, I found the defaultdict in collections which allows to specify defaults on dictionary creation, which I liked much more for this particular case.
Day 2 causing unexpected problems already! Ugly code this time, might try to refactor it later a bit.
Regarding what I've learned about Python...
A better understanding of its iterators, and in particular learnt about enumerate, which I'm sure will come handy more than once on this Advent of Code.
I've now created a simple template for each day to save some time on the initial boiler plate.
Regular expression day. Raw string literals, split, search and findall functions around regular expressions. Also looked into lambda definition in Python.
A bit to learn today around arrays. strings are arrays, which makes this easy. Also some more lambda, and some more practice with in.
First day of graphs with Python. I messed this one quite a bit in part 1, not realising the actual ask didn't care about transitive relationships between pages. Just got lucky my way of solving it actually worked. By part 2, I realised, which made the solution much simpler. I am not going to refactor this, rather leave the overcomplicated solution.
Regarding learnings... new for me have been the use of list() dict() set() intersection() and sorted(). All pretty basic stuff, but still useful. I am however feeling my code is very much not Pythonic. Not sure if I'll manage to improve that during this advent of code.
Quite bad and ugly code today, with lot of bad code duplication. Not proud of this one.
Specific new things I've used this day: match expression.
Quite a simple one today, hasn't given me the chance of using anything stricitly new to me in Python.
Another surprisingly straightforward day. Has let me take an initial look into classes in Python, defining operator behaviours and making them hashable. Also, how to use __name__ to know if a file is the main file being executed or if it is imported as a module.
Worst day so far, took me very long to correct my totally wrong approach to part B.
In Python learnings, mostly more dealing with classes.
Solution for part B required just a couple of small changes from the solution to part A, which is always nice.
In learnings, I've used list comprehension and list generators.
Cache day. Not much more to say.
Nothing really new today
Not much today either. I did look in a bit more detail into numpy, but didn't use anything new in the end
Weird part 2 today. I first had to do some manual examination of resulting grids before knowing what to look for.
One learning to highlight: if a function returns several values on a tuple, you can't just get the first one without explicitly getting the others, or it will actually contain the tuple itself. Quite obvious in retrospect.
Part 1 has taken me forever today due to some silly mistakes due to me writing ugly code. I really should know better.
Small learning today regarding how to measure elapsed time.
Hard to approach second star today! Learnings: bitwise operations, that I hadn't really used before in Python.
Always one or two Dijkstra problems every year. For part two I am almost certain there is a smarter way of doing it, looking at the current minimal path and checking if a new byte lies in that path or not. If it does, then you would just need to recalculate a path from the previous node to the next one. Instead of that, given the limited number of bytes, I've just gone with a kind of force brute approach, using a binary search in the problem space. Worked well enough.
Not much new in question of Python lessons here. I think I am now being better at using list comprehension and generators.
Well, that was a day of a couple of great ideas for the wrong question. Those wrong approaches at least let me learn more about regular expressions on Python.
Not much new learnt today. My code still doesn't feel pythonic to me.
I chose a bad day to try and force me to write more pythonic code. Part 1 wasn't too bad, part 2 took me many hours of basically rewriting to be able to optimise it properly.
Learnings: functools.cache to memoize out of the box instead of creating my own caches. That is handy! Lot of extra learning around lists, generators, iterators.
Not too hard today, even though I clearly haven't found the correct way of doing it. Just a bit of brute force is enough though. Have been using what I learned yesterday, trying to still write more pythonic code. And I have discovered 'namedtuple' and 'NamedTuple' which are very nice indeed.
More practice with sets and list comprehension mostly. Also learned about 'frozenset'. Code is still ugly though.
That was painful! Not ready to push my code for part 2 just yet. In the end I've done part of the solution manually, helped by the code to find where the problems were, but I want to finish it to actually produce the bits I've done manually.
Happy Christmas! QUick one, with a quick and dirty solution. I'm also pushing whatever I have for part 2 of day 24, even though it is still unfinished and requires manual work.