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Why does the order of the loops affect performance when iterating over a 2D array?
...2]
x[0][3]
x[1][0] etc...
Meaning that you're hitting them all in order. Now look at the 1st version. You're doing:
x[0][0]
x[1][0]
x[2][0]
...
Django queries - id vs pk
...ry key field i.e. you don't need to care whether the primary key field is called id or object_id or whatever.
It also provides more consistency if you have models with different primary key fields.
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Swift equivalent for MIN and MAX macros
...
With Swift 5, max(_:_:) and min(_:_:) are part of the Global Numeric Functions. max(_:_:) has the following declaration:
func max<T>(_ x: T, _ y: T) -> T where T : Comparable
You can use it like this with Ints:
let maxInt = max(5,...
Why do most C developers use define instead of const? [duplicate]
...== x, but if SCALE is an (extern) const, it will need to generate code to fetch the value and perform the multiplication because the value will not be known until the linking stage. (extern is needed to use the constant from several source files.)
A closer equivalent to using #define is using enume...
EntityType has no key defined error
... needs to be a CLS-compliant type, meaning unsigned types like uint, ulong etc. are not allowed.
This error can also be caused by configuration mistakes.
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What is `mt=8` in iTunes links for the App Store?
...nk itself (e.g. RSS Feed Generator, Search API,
Enterprise Partner Feed, etc.). This helps identify where the link
came from for your benefit, but doesn’t actually affect the end user
experience. This can be removed if necessary to tidy up the link.
Affiliate Specific Parameters
AT...
What should be the values of GOPATH and GOROOT?
...ct trees (e.g. git) with non-go files - e.g. images, scripts, build files, etc?
– Serge Merzliakov
May 17 '19 at 1:44
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Haskell, Lisp, and verbosity [closed]
...ros you can do with a higher-order function (and I include monads, arrows, etc.), but it might require more thinking (but only the first time, and it's fun and you'll be a better programmer for it), and
the static system is sufficiently general that it never gets in your way, and somewhat surprising...
Using $_POST to get select option value from HTML
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Use this way:
$selectOption = $_POST['taskOption'];
But it is always better to give values to your <option> tags.
<select name="taskOption">
<option value="1">First</option>
<option value="2">Second</option>
<...
C dynamically growing array
...ynamic array implementations work by starting off with an array of some (small) default size, then whenever you run out of space when adding a new element, double the size of the array. As you can see in the example below, it's not very difficult at all: (I've omitted safety checks for brevity)
type...