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Fastest way to list all primes below N
...t William Hanks for primesfrom2to, primesfrom3to, rwh_primes, rwh_primes1, and rwh_primes2.
Of the plain Python methods tested, with psyco, for n=1000000,
rwh_primes1 was the fastest tested.
+---------------------+-------+
| Method | ms |
+---------------------+-------+
| rwh_prime...
How may I sort a list alphabetically using jQuery?
I'm a bit out of my depth here and I'm hoping this is actually possible.
10 Answers
10...
Multiple Indexes vs Multi-Column Indexes
I've just been adding an Index to a table in SQL Server 2005 and it got me thinking. What is the difference between creating 1 index and defining multiple columns over having 1 index per column you want to index.
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Error type 3 Error: Activity class {} does not exist
I have an IntelliJ Android project, that I successfully imported to Android Studio 0.4.0. It works perfectly if I don't change anything in manifest. However, when I want to change the launcher activity and run, it fails with this error:
...
Why does range(start, end) not include end?
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You explain that range(x) should start with 0 and x will be the "length of the range". OK. But you didn't explain why range(x,y) should start with x and end with y-1. If the programmer wants a for-loop with i ranging from 1 to 3, he has to explicitly add 1. Is this reall...
How to convert an int to string in C?
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EDIT: As pointed out in the comment, itoa() is not a standard, so better use sprintf() approach suggested in the rivaling answer!
You can use itoa() function to convert your integer value to a string.
Here is an example:
int num = 321;
char snum[5];
// convert 123 to string...
IE7 Z-Index Layering Issues
...'re specifying it relative to other elements in the same stacking context, and although the CSS spec's paragraph on Z-index says a new stacking context is only created for positioned content with a z-index other than auto (meaning your entire document should be a single stacking context), you did co...
How can I make setInterval also work when a tab is inactive in Chrome?
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On most browsers inactive tabs have low priority execution and this can affect JavaScript timers.
If the values of your transition were calculated using real time elapsed between frames instead fixed increments on each interval, you not only workaround this issue but also can achiev...
How to check if PHP array is associative or sequential?
...kurO.
For the second question (checking whether the array is zero-indexed and sequential), you can use the following function:
function isAssoc(array $arr)
{
if (array() === $arr) return false;
return array_keys($arr) !== range(0, count($arr) - 1);
}
var_dump(isAssoc(['a', 'b', 'c'])); //...
Validate phone number with JavaScript
I found this code in some website, and it works perfectly. It validates that the phone number is in one of these formats:
(123) 456-7890 or 123-456-7890
...