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nonsequitur

50 karma · joined February 17, 2008

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nonsequitur··on Show HN: HyperLogLog in Zig
Yes: https://zigbin.io/771ac5
nonsequitur··on We want to make Nix better
Nix is turing complete (it can implement the Lambda Calculus), even conveniently so.
nonsequitur··on Looking at Zig Programming Language
Hint: It's `catch {}` instead of `catch { ... }`.
nonsequitur··on Finding the average of two unsigned integers without overflow
This doesn't work because you're not left-shifting (doubling) the carry. But when adding the shifted carry to (x ^ y) we're back to potentially overflowing the highest bits. The solution is to add the highest and the lower bits separately:

  lower = 0x7f7f7f7f;
  highest = ~lower;
  z = ((x & lower) + (y & lower)) ^ ((x ^ y) & highest);
Note this only improves performance for larger container integers.
nonsequitur··on How to use dig
You can directly query `getaddrinfo` with

  getent ahosts myhost
nonsequitur··on NSA's Puzzle Periodical
There's no assignment to the „m“ variables that would make your algorithm work in the general case.

im4w1l's strategy is just:

Player i returns (i - [Sum of the other players' suits]) % 4

(With i ranging from 0 to 3)

nonsequitur··on How to multiply polynomials in Θ(n log n) time
Thanks! That paper is available on the author's website: http://gi.cebitec.uni-bielefeld.de/people/zsuzsa/papers/Algo...
nonsequitur··on How to multiply polynomials in Θ(n log n) time
Can anybody guess in which way he used convolution for solving what is generally known as the change-making problem? Wikipedia [1] mentions a "probabilistic convolution tree", but that seems much more involved.

Edit: Solved. I've missed that the problem only deals with change amounts that can be reached with one or two coins. So a single convolution is sufficient in this specific case.

https://en.wikipedia.org/wiki/Change-making_problem

nonsequitur··on The C++ Programming Language (4th Edition)
I was dissappointed with the quality of the code and the final demo game. Also, it uses DirectX.

Here's an alternative: Dive into the GamePlay engine (https://github.com/blackberry/GamePlay/) and go through all the samples (https://github.com/blackberry/GamePlay/tree/master/samples), especially this collection of small feature demos (https://github.com/blackberry/GamePlay/tree/master/samples/b...). You'll get exposed to core concepts like Lighting, Terrain, Particles, 2D GUIs and Lua Scripting, all implemented from the ground up in C++ and OpenGL.

nonsequitur··on Google Blockly - a visual programming language
Take some of that time to figure out the math and the code becomes trivial:

  for (n = 1; n <= 20; n++) {
    window.alert(n << (n-1))
  }
A short explanation: http://mathbin.net/98435
nonsequitur··on 9 reasons to start using C++11
C++11 support in common compilers: http://wiki.apache.org/stdcxx/C++0xCompilerSupport
nonsequitur··on Students Ace Textbook Physics While Struggling With Basic Understanding (video)
The complete "Force Concept Inventory" test (PDF): http://shs.westport.k12.ct.us/physics/2007-2008/FCI-rv95.pdf http://bit.ly/8YeiOZ (mirror)