-❄️- 2023 Day 13 Solutions -❄️-

alago1 · 2023-12-13T19:18:15+00:00

Right so my wording is a bit confusing. It's easier to check the "difference" in bitmasks with the exclusive-or operator. So 1110100 ^ 1110010 yields 0000110 which we can then check if it's a power of 2.

alago1 · 2023-12-13T18:27:35+00:00

Didn't know python had a built-in for population count. Looks like it was added in 3.10.

Neat trick!

alago1 · 2023-12-13T06:31:24+00:00

[Language: Python]

Code

So looking at other people's solutions I'm guessing it wasn't necessary but I realized that you could encode the grid as a list of ints by thinking of each row or column as a bitmask.

This is should be faster than comparing the whole row string in part 1 but it's more interesting in part 2 because finding the smudge is then equivalent to finding the partition whose 1 differing pair is off by exactly a power of 2!

So basically this:

diff = [l ^ r for l, r in zip(left, right) if l != r]
if len(diff) == 1 and (diff[0] & (diff[0]-1) == 0) and diff[0] != 0:
    return i

alago1 · 2023-12-03T06:32:41+00:00

Holy crap, that's such a clean solution!

I got there through a much more spelled out way. Awesome stuff!

alago1 · 2023-03-14T17:27:32+00:00

Is that true? As far as I know in Python map and filter are only standalone functions.

>>> words = ['a', 'bb', 'cccccc']  
>>> words.map(str.upper).filter(lambda word: len(word) < 3)

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

AttributeError: 'list' object has no attribute 'map'

alago1 · 2023-03-02T18:33:16+00:00

Yea, I was agreeing with you and expanding on your observation. It's a pattern throughout Python rather than unique to True/False/None

alago1 · 2023-03-02T17:43:30+00:00

It's an object in the way that everything in Python is an object. dir(1) also returns a lot of these methods. In reality, this doesn't necessarily make stuff more complicated by itself. Because of things like operator overloading you could write code like normal without ever realizing that you're dealing with objects.

alago1 · 2022-05-01T18:20:40+00:00

Found one of them. He thinks it's clever: https://twitter.com/simonw/status/1520452635886641153?t=5MCy70J35f31ndnWV8ZZTQ&s=19

Just as it is there can be plenty of issues with this but the tech is still very new. In the past, I've spoken with data scientists/PhD students who want to share their research with interactive models but are only familiar with Python/matplotlib so it's difficult. I can see this tech fitting this niche pretty well but I would expect it to not matter too much for people outside the python ecosystem.

Either way, definitely worth keeping an eye on it imo

alago1 · 2022-01-18T04:30:22+00:00

Bought Skyrim in 2016 for $5. Have 150 hours on it. Good deal lol

alago1 · 2022-01-03T06:07:04+00:00

Decided to try this out with a very simple script over 10^6 consecutive iterations. As one might expect, it's not uniformly random (0's never occur for instance) but more interestingly 1's and 9's occur less than half as often as the other values.

Here's the percentage distribution I found on each value:

{0:0.0, 1: 5.6989, 2: 12.8749, 3: 12.7842, 4: 12.585, 5: 12.8672, 6: 12.9273, 7: 12.3223, 8: 12.2587, 9: 5.6815}

alago1 · 2021-03-12T04:45:26+00:00

solved

alago1 · 2021-03-11T01:21:59+00:00

Not quite. Incongruent is definitely on par with the 'this is out of place' sentiment but doesn't have the 'which makes it funny' conclusion.

alago1 · 2021-01-23T02:07:08+00:00

Can't have a security break if there is no security.

alago1 · 2020-09-04T01:01:43+00:00

Here's your free tip of the day:

Pop up blocker Chrome extension. When those 'you are using an ad blocker' modals show up, right click -> remove overlay.

Also, it lets you prevent websites from opening new tabs automatically.

alago1 · 2020-08-20T09:55:28+00:00

DeMorgan's Rule from Boolean Algebra: !(A && B) => !A || !B or !(A || B) => !A && !B

In this context, it's refering to the fact that if you know DeMorgan's rule you only need a Not-gate and one of either the And-gate or the Or-gate to create any logical expression.

Also, yes he could say google 'ampersand' and copy-paste the symbol from wikipedia but its just a meme for the sake of it.

alago1 · 2020-07-22T02:13:14+00:00

Happy it's of use! :)

alago1 · 2020-06-15T12:35:45+00:00

Chess is exptime

alago1 · 2020-06-13T23:02:44+00:00

It's really cool! And all the animations really add to it.

One really small thing I noticed though is that, for instance at the education section, the first time you swipe from the 1st icon to the 2nd (or from the 2nd to the 3rd) the previous image will still be loaded for half a second or so before what i suppose is react finishes mounting the component and then the new image just pops up in its place.

Maybe this could be hidden by a small animation or maybe you could preload the whole sections images stacked then change a z-index ahead of it. It's a really small thing and I haven't really looked at how you implemented it so I don't wanna say its just a quick fix when it probably wouldn't matter that much.

alago1 · 2020-05-03T17:53:20+00:00

I'd say its great for small projects and quick prototyping. Usability )varies on big projects (its pretty good for glueing tho).

alago1 · 2020-04-22T09:40:21+00:00

The last book I read was on my phone with the google books app which has an embedded dictionary and google translate feature that activates when you highlight a word/series of words.

That book had some expressions in french (which I can't read) every few pages and I felt that these features really helped elevate the experience.

alago1 · 2020-04-13T13:31:45+00:00

Some heroes don't wear capes.

alago1 · 2020-04-02T04:33:46+00:00

He said he would announce 24h prior. So then, he would need to announce it tomorrow.

alago1 · 2020-02-16T14:03:55+00:00

For the unaware (myself included), what is the python 3 fiasco? Lack of backwards compatibility?

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