Generated by Codex with GPT 5.6 Sol High

Quick facts

• Difficulty: HARD
• Problem: Custom LeetCode-style prompt: Count Nodes in a Distributed Tree
• Topics: Distributed Systems, Tree, Asynchronous Programming, State Machine, Idempotency

Problem gist

Every tree node runs in a separate process or on a separate machine. A node knows only its parent and its direct children, and it can communicate with them only by sending asynchronous messages.

Generated by Codex with GPT 5.6 Sol XHigh

Quick facts

• Difficulty: MEDIUM
• Problem: Construct Binary Tree from Preorder and Inorder Traversal
• Topics: Array, Hash Table, Divide and Conquer, Tree, Binary Tree

Problem gist

Two arrays describe the same binary tree:

• Preorder visits each node before its children: root, left subtree, right subtree.
• Inorder visits each node between its children: left subtree, root, right subtree.

The task is to rebuild and return the tree. Every value is unique, and the two arrays are guaranteed to describe the same tree.

Generated by Codex with GPT 5.6 Sol XHigh

A training environment is part of the model

The official Microsoft Research Blog published this post on July 30, 2026. Its central argument is that computer-use agents do not improve merely by seeing more synthetic websites or more demonstrations. They need environments that preserve the causal structure of real work: permissions, shared state, multi-step dependencies, error behavior, and consequences that remain coherent across screens and users.

Generated by Codex with GPT 5.6 Sol XHigh

Techmeme surfaced WIRED’s July 30 report, “Google’s Gemini Can Now Stomp Around as a Humanoid Robot,” about Google DeepMind’s attempt to move general-purpose AI out of chat windows and into machines with arms, hands, and legs. The eye-catching demonstrations show humanoids tidying shelves, tying bags, and handling lightbulbs. The deeper advance is architectural: Google has assembled perception, planning, motor control, and adaptation into a layered system that can operate several kinds of robots rather than one machine trained for one fixed routine.

Generated by Codex with GPT 5.6 Sol XHigh

Artificial-intelligence sovereignty sounds like national control over models, chips and computing infrastructure. For most countries, that goal is unrealistic. The frontier is increasingly dominated by America and China, whose governments can shape not only how advanced models are made safe, but also who is allowed to use them. The practical challenge for everyone else is therefore to reduce vulnerability without wasting fortunes on an impossible race for total independence.

Generated by Codex with GPT 5.6 Sol XHigh

Iran rejects Oman’s 50-50 Hormuz shipping plan (r/worldnews)

• MrBobSacamano: Honestly, this whole saga has only served to illustrate to the Gulf states, and the rest of the world, that infrastructure needs to be built to just bypass the Strait completely. There is already initial planning underway to expand infrastructure like Saudi Arabia’s East-West pipeline, which is a start.
• PopTartPounder5: I’m assuming all the Middle East countries are planning pipelines to avoid the strait of Hormuz at this point
• Efficient_Dark1977: The Strait of Hormuz is IRGC’s last remaining lifeline. Without it, there will be no more nuclear deals and they have no more legitimacy. This has always been their doomsday weapon, and they have now deployed it. They will never let go of it peacefully.

Iranian rapper sentenced to death over January protests, source says (r/worldnews)

• TheParadoxigm: The source said Navab Safavi had two lawyers, but neither was granted access to the case file or given an opportunity to defend him. His trial was also held in absentia.
• PopTartPounder5: Charged with “waging war against god” wtf
• catscanmeow: theyre in a really precarious moment now too because once their allies supply them with high tech crowd control devices, drones, etc, there’s no way out of fascism/dictatorship.

What book is absolutely flawless and impossible to put down once you start it? (r/AskReddit)

• Historical-daffodil: The writing in Charlotte’s Web is exquisite. Reading it to my kids as an adult was a powerful experience.
• Popeholden: The only book I ever read cover to cover in one sitting is The Martian by Andy Weir. Something about the compelling human story mixed with plausible scientific solutions made it fascinating and very consumable.
• Bonesaw_1987: Devil in the White City. Absolute ripper of a history book.

What’s a boring business that quietly makes its owner rich? (r/AskReddit)

• Puzzleheaded-Fun2740: Commercial grease trap cleaning. Restaurants are legally required to have them cleaned. It’s disgusting work so nobody wants to do it — zero competition. Guy who does our local restaurants charges \$300-500 per stop, does 8 a day, drives a Porsche. Every customer is recurring forever because it’s a health code requirement, not optional.
• Rapper_Laugh: I’ve always thought this about the private parking lots near airports that are basically just an exit/entry machine and a huge slab of cement. I have to imagine those things are pure profit.
• Chiplore: Knew a guy who rented concrete street dividers to the city used during construction. No special storage and virtually indestructible. City would move them from one site to the next. Like all cities, the road construction is never ending.

What is an unsexy, raw reality of a long term marriage/relationship that nobody warns you about? (r/AskReddit)

• BenightedBuckaroo: Sometimes you won’t like each other. It doesn’t mean it’s over. You just need to find new ways to reconnect. Also, you’re probably just really tired.
• IHeartWichita: We’re in our late 70s now and spend a lot of time at doctors appointments. It only gets worse in your 80s and beyond. You’ll need each other in your worst and most vulnerable moments.
• Reasonable-Mischief: You gotta be able to be good coworkers. Not being able to carry responsibility together will break you

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Employees are using AI to do each other’s work (Blind)

• AndruJasru (Amazon): This just shows that people think other people’s jobs are easy. PMs think they don’t need engineers because they can just type in prompt and generate code slop. Eng thinks they don’t need PM bc they can just generate document slop. They both think they don’t need design bc they think their slop looks good enough. Leadership thinks they don’t need any of the above bc they can type into chat box and make tokens go brrr. So they actually laid off everyone
• Whacksmang (Zillow Group): they all trying to code and don’t know what a loop is or what a conditional is. Assistants using AI to code up dashboards connected to production data is wild.. no compliance, no architectural thought.. nothing can scale but heck.. they are productive.
• fallguy312 (ex-Amazon): lol yeah I love it when the PMs copy paste our eng docs into Claude to “provide feedback” and then also generate full docs themselves

Amazon AGI Layoffs - Why? (Blind)

• mT37j (Google): Amazon doesn’t do research things where the ROI isn’t clear. These people didn’t have any results to show during their last review.
• tanho (Amazon): These are still the ripple effects of Rohit leaving last December and AGI being restructured. The foundation model is now being built by a small team under Peter Abbeel, many hired from Google Deepmind, which is a radical departure from Rohit’s previous approach, where hundreds of people were collaborating on this.
• boredddddd (Microsoft): I don’t like Amazon overall but this is one of the smartest thing they have done. AGI doesn’t serve amazon’s product and businesses in any way and there is no point pouring money into a leaky bucket.

Google Coding Bar is insane!!! (Blind)

• bdFp52 (Meta): NGL dude. I got G offer 2 week ago. Idk how TF I solved my coding problems, I came home, looked back and was in awe of how I even did it. I really was just wired. Almost felt like someone else did it through me, I was just a vessel. So I feel this.
• pothos🍃 (ex-Chime): Joining Google is now a matter of luck. Nothing else.
• NRQf45 (Microsoft): The point is usually to have difficult to impossible problems to see how one thinks and approaches problems because that’s the job. You don’t usually get handed a clear straightforward obvious and precise spec

Is it illegal to trick the US government into wiping your phone during a questionably legal search | The case of a traveler who allegedly entered a ‘duress password’ to wipe his phone raises a legal question with no easy answers (r/technology)

• OftTopic: The part I found the most alarming was that Customs claimed that the interrogation room in the Atlanta airport was not part of the United States. Therefore citizens have no rights.
• kstargate-425: I was being harrassed and intimidated by government goons with guns and I mistakenly gave them the wrong password as they rushed me and entered it quickly 🤷‍♂️
• not_the_fox: They asked for a code while detaining him, not mirandizing him, and not allowing him a lawyer. He did the best he could under the circumstances. It’s unreasonable to expect cooperation. If they want to search the phone they could but they started asking for codes from someone detained while refusing them legal counsel.

Willie Nelson Urges Americans to Fight the Construction of Data Centers: They ‘Only Destroy the Environment Around Them’ (r/technology)

• mrbasedballed: He’s right. I’m witnessing it firsthand. These techno-fascists sure in the hell did a great job of getting their henchmen into local government to push this shit through. Want to complain at a town meeting? Get arrested. We’re not angry enough yet.
• alsatian01: How about we limit their size, require them to use actual coolant instead of water, and derive a significant amount of their power from wind and solar?
• postitnote: I think we can find a compromise where we build datacenters next to people who believe in minimal regulation and state interference of free markets. Quite easy to find, they are next to farmlands typically.

Generated by Codex with GPT 5.6 Sol XHigh

The Pragmatic Engineer surfaced the piece in “Formal methods with Hillel Wayne”, a conversation about a question made more urgent by AI-generated code: if software can be produced faster than people can understand it, what should teams trust as evidence that it is correct?

Generated by Codex with GPT 5.6 Sol XHigh

Andrew and Tristan Tate to remain in jail until next extradition hearing (r/news)

• mudturnspadlocks: Good, they can get used to what it’s going to be like. Although UK prisons might be a little better.
• AhBee1: Lets imprison all sex trafficking pedos.
• HipHopDropper: They are so toxic even Trump doesnt wanna have anything to do with them. They better not get another lifeline.

Pentagon reports more than 600 Iran war casualties in quiet database update (r/news)

• Dwayla: Remember when Trump called them “suckers and losers”, he wasn’t joking.
• Blissfully: American youth fighting wars for old men
• LUCKYxTRIPLE: Casualties here includes injuries, not just deaths.

Zookeepers of reddit, which animal is way less fun to care for than most people would expect? (r/AskReddit)

• Turbulent-Language20: Prairie dogs. Only enclosure that I went into armed (with a broom lol). Those little fuckers will launch themselves at you like demonic little missiles. And with their labyrinth of tunnels you never know where they will pop up. Most terrifying game of whack a mole ever (no I never hit them, the broom was more of a shield or a deterrent).
• GetBent616: My personal least favourite was red pandas. Dont get me wrong, theyre so cute. Beautiful creatures. But my god they shit so much. Its equal parts unreasonable and impressive that so much can come out of an animal that size in 24 hours.
• ca77ywumpus: I got to chat with the head keeper of the large carnivores at a zoo once. He said that the Black Footed Cat is a vicious little demon. When they clean their enclosure the cats are kept in a holding cage, and they spend the entire time throwing themselves against the door, trying to murder the keepers. The tigers might hurt you on accident because they’re so big, but the teeny little Black Footed Cats know they are Nature’s perfect killing machines, and will take any chance to remind you.

What’s a product where the cheap knock-off version is somehow unironically better than the expensive original? (r/AskReddit)

• The_Kraken: My local grocery store, HEB, will not release a store brand product unless it beats the leading name brand in a blind taste test. Their store brand products are outstanding across the board.
• 4oclocksundew: Pregnancy tests. The dollar tree ones are the exact same kind the doctor will use when you go to confirm. The expensive digital tests are less sensitive. They are more likely to give you a false negative test if youre testing early.
• DontBlameMe4It: Any sports jerseys that Fanatics make. The cheap \$20 counterfeits are better quality than ANY Fanatics jersey.

Which cancelled celebrity hurt the most because you actually liked them before it all came out? (r/AskReddit)

• BillG8s: All of the kids from That 70s Show minus Topher.
• jrw6200: Bill Cosby. Grew up (1960s-70s) listening to his records, still outraged at the thought of what a monster he really was the whole time, etc.
• MiyagiJunior: Neil Gaiman. I met him in person a few times and he was always super nice and friendly. What I read about him was so terrible that as much as I tried to hold on to my positive sentiments towards him, I couldn’t.

Generated by Codex with GPT 5.6 Sol XHigh

Career hack: Stop being an engineer and switch to management. (Blind)

• nebula12 (Amazon): Truly spoken like an L3/L4 engineer. Dealing with code is way simpler than dealing with people. What you see is a fraction of what they do
• PromoNever (Google): It’s non stop meetings. Both during and after working hours. There’s no, eh, I’ll just code at 2am. The meetings are endless!!!
• hfWh13 (Cohere): Tell me you’ve never been a manager without telling me.

Can You Survive as an IC After 40 in the AI Era? (Blind)

• heXm60 (Google): I feel AI makes it much easier for senior IC to perform because you have an army of AI agents that can help you deliver much faster since you have done those things 10000 times
• HGIK28 (DigitalOcean): AI will kill more managers than senior ICs. You don’t need that many people manager since every IC is an agent manager.
• Turnusdown (Apple): My team at Apple literally has 70 year old SWEs trying to vibe code.

Google headcount grew 6% in the last year (Blind)

• Ugsgave (Google): We have a lot less contractors and way more of the new headcount is in cheaper countries
• lifeflow (Netflix): I thought AI is going to do the jobs!
• gewgul (Google): It’s unacceptable. Absolutely ridiculous. We need to lay more people off. Expect mass layoffs in the coming months. We are over hiring severely.

SpaceX Investors in Meltdown Over All the Money They’ve Lost (r/technology)

• drummer820: If only someone had warned them besides EVERYBODY
• BeachZed: The money isn’t lost, they gave to Elon and his insider investors.
• anti-ism-ist: No crying in the casino

If open weight models are the future, U.S. AI companies are going to have a hard time (r/technology)

• mykepagan: I work in the industry. I’m seeing large financial institutions who are extremely interested in smaller open models because they see much value in fine tuning them with the mountains of proprietary data that they have accumulated for decades. The desire is for a custom model that is very specific to a task like prediction or anomaly detection. And they absolutely don’t what to give that data to any third-party AI company.
• PhiNeurOZOMu68: Spent extremely little tokens for Claude helping me tune a local model on my pc - now I just use the local model without shelling out \$200 a month. It’s amazing. Big US AI companies are going to fail. China already won.
• seriousgourmetshit: The only reason the US AI companies are stressing safety concerns so much lately, is so they can get Chinese models banned. They dont give a fuck about you or your safety.