HN user

DannyB2

2,224 karma

If one of the production server's power supply has caught fire, best practice is to schedule a meeting to determine whether DevOps should fix this, or the software team should issue a software patch to correct the problem in order that we can close this ticket as quickly as possible.

Posts0
Comments563
View on HN
No posts found.
Parsing Integers in C 8 months ago

Being liberal in what you accept is fine, as long as what you accept is precisely documented. But then, is that actually "being liberal"?

Better advice is to not do something unexpected -- even if that unexpected result is clearly documented, but someone did not read it.

0ThreadHN
Solving Every Sudoku Puzzle (2006) 8 months ago

It was a denial of service attack, not in the sense of soaking up my brain cells solving puzzles, but in causing me to devise and program my own solver. (In Java, text console only.) Once I wrote a solver, I felt as if I had solved all puzzles.

Then I got interested in devising puzzles with multiple solutions. Not too difficult. But making a few puzzles with two solutions was fun.

Experiment_203(

   " 1 . . | 2 . 8 | . . 9 "+
   " . 8 . | . . . | . 3 . "+
   " . . 7 | . 1 . | 2 . . "+
   //------+-------+--------
   " 4 . . | 1 2 3 | . . 6 "+
   " . . 2 | 4 5 6 | 9 . . "+
   " 6 . . | 7 8 9 | . . 4 "+
   //------+-------+--------
   " . . 6 | . 4 . | 8 . . "+
   " . 2 . | . . . | . 7 . "+
   " 9 . . | 8 . 2 | . . 1 "
  ),
// Solution #1. Found in 0 days 00:00:00.004.

// 245 boards examined so far.

   1 6 5 | 2 3 8 | 7 4 9
   2 8 4 | 6 9 7 | 1 3 5
   3 9 7 | 5 1 4 | 2 6 8
   ------+-------+------
   4 7 9 | 1 2 3 | 5 8 6
   8 3 2 | 4 5 6 | 9 1 7
   6 5 1 | 7 8 9 | 3 2 4
   ------+-------+------
   7 1 6 | 3 4 5 | 8 9 2
   5 2 8 | 9 6 1 | 4 7 3
   9 4 3 | 8 7 2 | 6 5 1
// Solution #2. Found in 0 days 00:00:00.001.

// 287 boards examined so far.

   1 6 5 | 2 3 8 | 7 4 9
   2 8 4 | 9 6 7 | 1 3 5  // <-- 9 6 7 instead of 6 9 7
   3 9 7 | 5 1 4 | 2 6 8
   ------+-------+------
   4 7 9 | 1 2 3 | 5 8 6
   8 3 2 | 4 5 6 | 9 1 7
   6 5 1 | 7 8 9 | 3 2 4
   ------+-------+------
   7 1 6 | 3 4 5 | 8 9 2
   5 2 8 | 6 9 1 | 4 7 3  // <-- 6 9 1 instead of 9 6 1
   9 4 3 | 8 7 2 | 6 5 1


   2 total solutions found.
   304 total boards examined.
   Total time 0 days 00:00:00.041.
Then I got to looking at difficult puzzles on the web. Apparently AI escargot is the world's most difficult. (And the site http://www.aisudoku.com/index_en.html says I can't publish the board). So I'll only publish the stats of applying my solver to it.
  Solution #1.  Found in 0 days 00:00:00.029.
  3,906 boards examined so far.

  1 total solutions found.
  7,832 total boards examined.
  Total time 0 days 00:00:00.085.
0ThreadHN
The fastest way to detect a vowel in a string 1 year ago

Assume use of 8 bit characters. Declare a constant 256 entry array pre-filled with all False except for the five (or six) vowel characters. This is baked into the code and not initialized at runtime.

Now for each character c in the input string, simply do an array index and see if it is true (a vowel) or not. This avoids either five conditionals, or a loop over the string 'aeiou'. The vowel test is constant time regardless of the character value.

0ThreadHN
English Multinyms 1 year ago

Data: Captain, the censors have detected incoming copyright infringement notices.

Riker: Shields up!

0ThreadHN
English Multinyms 1 year ago

Kneel Neal Neil

Knight Night Nite

Knot Naught Not

Lager, Lauger (a last name), Logger

Macs Mac's Macks Maks Max

Tends Tens Tins

Threw Through Thru

Ware Wear (clothing), Wear (diminished by use) We're Where

Your You're Yore

0ThreadHN
How to Use the Foreign Function API in Java 22 to Call C Libraries 2 years ago

I once (2016 ish) used a serial-port library for Java. Needed to be cross platform desktop app for Linux, Windows and Mac (in that order, all on x86/64). And it was. I have forgotten the name of the library project I included, but it included DLL binaries for the platforms we were targeting.

0ThreadHN
World Radio History Archive 2 years ago

FYI . . .

Download old BYTE magazines from here: https://www.americanradiohistory.com/Byte_Magazine.htm (but note URL has changed to worldradiohistory) https://www.worldradiohistory.com/Byte_Magazine.htm

Or higher quality scans here: https://archive.org/details/byte-magazine

Or Popular Electronics: https://www.americanradiohistory.com/Popular-Electronics-Gui...

Creative Computing: https://archive.org/details/creativecomputing

It's like a trip back in time.

BYTE magazine, April 1980, page 115.

NEW HIGH-SPEED COMMUNICATIONS BUS: Xerox Corporation recently made a public announcement of a new concept of processor-to-processor communications intended for an office environment. This novel concept is called "Ethernet", and is a result of some of the work being done in their research labs. In this concept, a single coaxial cable is used as a high-speed communications bus between all processors; communication protocol is handled through software or software supplemented by special-purpose hardware. Rumor has it that an Ethernet processor is now being developed by some form of joint arrangement between Xerox and Intel.

0ThreadHN
Add coffee stains to LaTeX documents (2021) 2 years ago

Because that is a hardware fix.

Why fix in hardware what can be fixed in software? A simple Latex package could add hydrophobic coating feature to the document file.

Next: the device driver team will be tasked with a software patch to correct for the burned out light bulb on the device.

0ThreadHN
Could an industrial civilization have predated humans on Earth? 3 years ago

If there were an industrial civilization here before us (modern humans) then it would be astonishing that in all of the fossils we have discovered, we've never yet discovered a single ancient nut, bolt, screwdriver, wrench, etc. Not one single wire or cast metal part.

As per the article, that civilization would have to predate all of the vast history of evolution that we know of. Wouldn't some higher life forms from such an earlier civilization have been in the fossil record?

0ThreadHN
Do What the Fuck You Want to Public License 4 years ago

I would prefer a version of the license that did not use fowl language. Fowl language is not suitable for my porpoises.

Beyond that, it would be nice if the license expressly granted unlimited copyright and patent permissions so that this is not assumed from the brief language of the license.

A bad actor could try to argue that he did NOT give you patent rights. Nothing in the license said so. You could argue that the license should be interpreted broadly to include that. Thus there is now a legal conflict.

I would prefer a license that is more explicit in exactly what legal rights it grants.

This reminds me of the short lived "no license" movement of some years back. If your code doesn't have a license, I'm not going to touch it with a ten foot pole. Nothing give me permission to use it. But you say "I'm giving it to you. I wouldn't sue you. I promise!" How about if you're really such a good guy, putting that promise in writing (it's called a license).

0ThreadHN
How UTF-8 Works 4 years ago

There is an error in the first example under Giant Reference Card.

The bytes come out as:

0xF0 0x9F 0x87 0xBA 0xF0 0x9F 0x87 0xBA

but the bits directly above them all of the bit pattern: 010 10111

0ThreadHN