I also really liked day 17, because at one point the solution for part 2 just clicked and now it makes so much sense.

I think my favorite was the full adder on day 24. Even though I only solved part 2 manually, it was still a lot of fun to reverse an actual full adder and get familiar with all the required logic gates.

I also solved part2 manually today, by outputting the correct addition and program output in binary and then reversing the path for all wrong outputs.

Then I just had to compare that to the formulas for a full adder and I found my swaps pretty quickly that way.

I did all of this in Kotlin and on paper, with a handy helper method to construct the paths.

It’s at the very bottom of this file on Github.

I suspect that comparing the bits and then comparing the paths to the full adder formulas can also be done ‘automatically’ decently easily, but I was too lazy to implement that today.

Kotlin

Part1 was pretty simple, just check all neighbors of a node for overlap, then filter out triples which don’t have nodes beginning with ‘t’.

For part2, I seem to have picked a completely different strategy to everyone else. I was a bit lost, then just boldly assumed, that if I take overlap of all triples with 1 equal node, I might be able to find the answer that way. To my surprise, this worked for my input. I’d be very curious to know if I just got lucky or if the puzzle is designed to work with this approach.

The full code is also on GitHub.

class Day23 : Puzzle {

    private val connections = ArrayList<Pair<String, String>>()

    private val tripleCache = HashSet<Triple<String, String, String>>()

    override fun readFile() {
        val input = readInputFromFile("src/main/resources/day23.txt")
        for (line in input.lines()) {
            val parts = line.split("-")
            connections.add(Pair(parts[0], parts[1]))
        }
    }

    override fun solvePartOne(): String {
        val triples = getConnectionTriples(connections)
        tripleCache.addAll(triples) // for part 2
        val res = triples.count { it.first.startsWith("t") || it.second.startsWith("t") || it.third.startsWith("t") }
        return res.toString()
    }

    private fun getConnectionTriples(connectionList: List<Pair<String, String>>): List<Triple<String, String, String>> {
        val triples = ArrayList<Triple<String, String, String>>()
        for (connection in connectionList) {
            val connectionListTemp = getAllConnections(connection.first, connectionList)
            for (i in connectionListTemp.indices) {
                for (j in i + 1 until connectionListTemp.size) {
                    val con1 = connectionListTemp[i]
                    val con2 = connectionListTemp[j]
                    if (Pair(con1, con2) in connectionList || Pair(con2, con1) in connectionList) {
                        val tripleList = mutableListOf(connection.first, con1, con2)
                        tripleList.sort()
                        triples.add(Triple(tripleList[0], tripleList[1], tripleList[2]))
                    }
                }
            }
        }
        return triples.distinct()
    }

    private fun getAllConnections(connection: String, connectionList: List<Pair<String, String>>): List<String> {
        val res = HashSet<String>()
        for (entry in connectionList) {
            when (connection) {
                entry.first -> res.add(entry.second)
                entry.second -> res.add(entry.first)
            }
        }
        return res.toList()
    }

    override fun solvePartTwo(): String {
        val pools = getPools(connections)
        println(pools)
        val res = pools.maxByOrNull { it.size }!!
        return res.joinToString(",")
    }

    // will get all pools with a minimum size of 4
    // this method makes some naive assumptions, but works for the example and my puzzle input
    private fun getPools(connectionList: List<Pair<String, String>>): List<List<String>> {
        val pools = ArrayList<List<String>>()
        val triples = tripleCache
        val nodes = connectionList.map { listOf(it.first, it.second) }.flatten().toHashSet()

        for (node in nodes) {
            val contenders = triples.filter { it.first == node || it.second == node || it.third == node }
            if (contenders.size < 2) continue // expect the minimum result to be 4, for efficiency

            // if *all* nodes within *all* triples are interconnected, add to pool
            // this may not work for all inputs!
            val contenderList = contenders.map { listOf(it.first, it.second, it.third) }.flatten().distinct()
            if (checkAllConnections(contenderList, connectionList)) {
                pools.add(contenderList.sorted())
            }
        }

        return pools.distinct()
    }

    private fun checkAllConnections(pool: List<String>, connectionList: List<Pair<String, String>>): Boolean {
        for (i in pool.indices) {
            for (j in i + 1 until pool.size) {
                val con1 = pool[i]
                val con2 = pool[j]
                if (Pair(con1, con2) !in connectionList && Pair(con2, con1) !in connectionList) {
                    return false
                }
            }
        }
        return true
    }
}

I did try that at first, but it didn’t really work the way I wanted it to. That’s probably also because our implementation from school was a bit odd.

This program is a client for the very solid Tvheadend TV streaming server. Tvheadend supports pretty much any source you can think of, but is a little more complicated to setup.

Tvheadend is a selfhosted service meant to be run on your own server with your own TV dongles / IPTV channels / etc.

If you only want to watch TV on your PC, doing so with something like Kodi is probably a better idea, as Kodi also supports USB tuners and is simpler to setup (doesn’t require a separate server).

I was pretty neutral towards Ubuntu, up until an automatic system update removed my deb Firefox and replaced it with the snap version, even though I specifically set the apt repo to a higher priority.

The entire reason I left Windows is because I don’t want (for example) Edge shoved down my throat after every update, and yet Ubuntu has gone and done the exact same thing with snaps.

After literal hours of fighting, the only solution I found was to fully disable automatic updates. With Pop OS I have all the benefits of Ubuntu, but I also get a company (System76) that does cool stuff and doesn’t try shoving snaps down my throat.

Adding to what others here have already said, I’d definitely download Signal and see if you can get any people to move from WhatsApp/Telegram/whatever to Signal.

I don’t know much about iOS apps, but you could look into more privacy focused YouTube clients, and possibly 2FA clients too (although that’s a bit of a controversial topic on iOS AFAIK).

I saw you mention in another comment that you use Amazon Alexa for smart home appliances. Depending on interest in selfhosting / time / motivation to move away from Amazon, you could look into using Home Assistant instead. It even has a Lemmy community: !homeassistant@lemmy.world.

Yep my mistake, I confused ShadowSocks with Cloak.

I’m afraid your best bet here will be using WhatsApp.

Edit:
FindMy (for Android) might also be usable for that, but honestly if you just want it to work I’d still vouch for WhatsApp.

Signal supports a single momentary position, but not live location.

What worked for me at my old school was using a ShadowSocks proxy. Basically what this does, is it takes all your traffic and just makes it look like random https traffic (AFAIK). ShadowSocks is just a proxy. The description fits the Cloak module, mentioned below.

I believe multiple VPNs support this, for me with PIA VPN it’s in the settings under the name “Multi-Hop” (PIA only supports this on the Desktop App, not on mobile).

This technique is pretty much impossible to block, unless you ban every single VPN ShadowSocks Proxy IP. If that is the case for you (chances are practically 0), you could also selfhost ShadowSocks in combination with the Cloak module, however this method is a lot more complicated.

If the main battery isn’t “meant to be replaced”, it will often act as the CMOS battery (e.g. MacBooks have been doing this since roughly 2008).

I find it even more puzzling as surely it has to be a decent increase in server demand to constantly be streaming video. How can that be worth it??

+1 on OnlyOffice, it has 1:1 formatting compatibility with Microsoft Office. Unlike LibreOffice, it doesn’t have to translate documents between odt and docx in the background.

In the same vein, OnlyOffice has poor compatibility with odt files etc.

Quite a few cars also still have a SIM card hidden somewhere, which can be removed. The location of it varies widely though and they’re usually pretty hard to find.

Yesss fcast looks incredibly promising. Sadly the only app implementing it seems to be GrayJay, I really hope it will catch on more.

Not OP, but this instantly made me think of the worst-case scenario PDFs I stumbled upon on Lemmy recently.

TVHeadend is the way, I’ve been running it with a USB satellite tuner for 5+ years. Setting it up can be a little confusing, but once it’s running you pretty much never have to touch it again.

As for clients, there’s a Jellyfin plugin, however it seems to not work for me right now.

My client of choice is Kodi with the TVHeadend plugin, and that works great. If you still want Jellyfin integration, you could just add your recordings folder as a library in Jellyfin.

Could I purchase two different brand drives and use them with btrfs?

I don’t quite remember the source for this, but I believe I read some time ago that it’s actually a good thing to have separate drives. The reasoning is, if you buy two identical drives (at the same time), the likelyhood of both drives failing around the same time is severely higher.

This is then amplified by the fact that rebuilding a RAID puts a lot of strain on the non-dead drive, so if ie. drive 1 dies and drive 2 is about to die, the strain you put on drive 2 in order to rebuild your RAID onto drive 3 might kill drive 2 before you even finish rebuilding your RAID.

Again, this is just from my memory, it might be worth doing some more research on.

I’d assume it won’t, you can always just test it out though. There might be some setting for those timeouts in the Steam-steamdeck settings.