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calfuris

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A problem in NP can have a (positive) solution verified in polynomial time. That's it. Requiring more than polynomial time to solve isn't part of the definition, and in fact it's an open question whether any problems in NP require more than polynomial time to solve.

Every single problem in P is in NP. What is believed but unproven is that some problems in NP are not in P.

Hard mode forces most people to play smarter than they usually would. I'm not sure if that's the same as being easier. Hard mode is certainly harder for a skilled player, because that player could play normal mode as if it were hard mode but without having to worry about avoiding hard mode traps like _IGHT or SHA_E--if they encounter such a scenario they can just play known-bad words that check several possible solutions at once (e.g. FIRES for _IGHT to check FIGHT/RIGHT/EIGHT/SIGHT).

"Ghoti" is an artificial example that doesn't actually work if you account for the way positioning affects pronunciation. Pull up a list of words that start with "gh": none of them (unless "ghoti" itself is on the list) start with an /f/ sound. You'll find the same for words ending in "ti" and the /ʃ/ sound.

I recommend asking people how "ough" is pronounced instead. Cough, bough, though, thought, through, thorough, hiccough--enough!

What are you talking about re: space shuttle and tens of millions?

GP was almost certainly referring to "They Write the Right Stuff," an old article that is pretty well known in spaces like this. It discusses a process that (a) works extremely well (the engine control software was ~420 kLoC with a total of 17 bugs found in a window of 11 versions) and (b) is extremely expensive (the on-board shuttle software group had a budget of ~35 million per year in mid-90s dollars).

It's not actually optimal. Each check should account for all previous feedback, but it may be optimal to make a known-incorrect guess and trade the chance of winning with that guess for additional information.

For example, if your first guess on wordle is BOUND and you learn that the word is _OUND, you know the answer is one of FOUND, HOUND, MOUND, POUND, ROUND, SOUND, WOUND. Satisfying all previous feedback leaves you checking those one at a time and losing with probability 2/7. Or you could give up the 1-in-7 chance of winning in 2 and trade it for certainly winning in either 3 or 4: HARMS checks four of those options, and WHOOP identifies the remaining three.

I don't see wires as a problem. Wireless accessories are slightly more convenient when you're moving the computer around, which is why my work laptop has a wired keyboard plugged into the dock and a wireless mouse with the receiver plugged into the laptop directly, but that's not a concern with my desktop so I go wired there.

I don't know exactly where to draw the line on "the vast majority," but surely it must be higher than the bar for a simple majority, which is "more than half." If you want to describe something in the lead but under the 50% mark, the word you're looking for is "plurality."

The Moon's gravity isn't just pulling on the water, it's pulling on the Earth as a whole. It's pulling more on the Earth as a whole than on the water on the far side. In the Earth's frame of reference, that looks like it is pushing the water on the far side away a little bit.

I'd rephrase the sell as "now people who are used to doing the wrong thing and risking vulnerabilities can do the right thing without any extra effort," with a footnote about the difference in types allowing libraries to force the change.

My favorite math professor said "your homework is as many of the odd-numbered problems as you feel like you need to do to understand the material" and set a five minute quiz at the start of each lecture which counted as the homework grade. I can't speak for the other students, but I did more homework in his classes than any of the other math classes I took.

Even in that case I'd be hesitant to open a CSV file in excel. The problem is that it will automatically apply whatever transformation it thinks is appropriate the moment you open the file. Have a digit string that isn't semantically a number? Too bad, it's a number now, and we're gonna go ahead and round it. You didn't really need _all_ of the digits of that insurance policy number, did you?

They did finally add options to turn off the common offenders, but I have a deeply ingrained distrust at this point.

If something was caused by pilot error, there's nothing you can really do except shrug and hope it doesn't happen again. It's an intuitively appealing explanation, and usually wrong. The aviation community has spent decades rejecting that instinct and looking for contributing factors that can be addressed. Those other factors are almost always present, and improvements can then be made. The net result of this process is that aviation has become incredibly safe, which would not have happened if people were content to say "eh, it was probably pilot error."

All else being equal, two access methods are strictly less secure than a single access method. But is all else equal? I suspect that there are quite a few people who are willing to use a long, complicated password occasionally but who won't put up with that for passwords that are used frequently. If those people use better passwords when they can use a PIN to make routine access easy, that's a win.

No, the statement was that ".net and .com are still pulling 80% of their weight when it comes to cybercrime." I read that as saying that .net and .com domains show up in cybercrime 80% as often as would be expected if all TLDs were equally likely to be used for cybercrime.

I disagree with this on multiple levels. For one, the word "berry" has multiple definitions, and I don't see why the botanical definition should be the only one that counts. If anything, the culinary one should have primacy, as that is the one that is far more relevant to far more people. Botanical jargon is useful to botanists but not very useful in general. And to descend to pedantry, blueberries should not have been on your list of examples. They are berries in both the culinary and the botanical senses of the word.

Percentages are incommensurable with most things, including other percentages in the general case. They are percentages _of something_ and in general the only way you can do addition, subtraction, or comparison is to identify the referent and multiply it out first (the special case is when the other value involved is another percentage with the same referent). So in math class, when you see 20%, you translate it to ".2 _times something_", which is not a value that can be added to 10. You have to figure out what to multiply it by first. In the case of 10+20%, it would be reasonable to assume 20% of 10, which is how you get 12. It would also be reasonable to ask "20% of what?" 10.2 is 10 + 20% of 1, which requires an explanation of how that 1 got involved.

New scientific models tend to look very much like the older models in some relevant limit, even when they are fundamentally very different. Einstein's relativity looks a whole lot like Newton's relativity at low speeds. Large collections of quantum-mechanical particles tend to behave classically. This is not an accident of history—the old models worked in some domain, which is why they became accepted models. I will counter your Pratchett quote with one from Asimov:

"When people thought the earth was flat, they were wrong. When people thought the earth was spherical, they were wrong. But if you think that thinking the earth is spherical is just as wrong as thinking the earth is flat, then your view is wronger than both of them put together."