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Fastest way to list all primes below N
This is the best algorithm I could come up.
35 Answers
35
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CSS selector for first element with class
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This is one of the most well-known examples of authors misunderstanding how :first-child works. Introduced in CSS2, the :first-child pseudo-class represents the very first child of its parent. That's it. There's a very common misconception that it picks up whichev...
What's “P=NP?”, and why is it such a famous question? [closed]
The question of whether P=NP is perhaps the most famous in all of Computer Science. What does it mean? And why is it so interesting?
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What does “dereferencing” a pointer mean?
Please include an example with the explanation.
6 Answers
6
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How to increment a pointer address and pointer's value?
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First, the ++ operator takes precedence over the * operator, and the () operators take precedence over everything else.
Second, the ++number operator is the same as the number++ operator if you're not assigning them to anything. The differ...
Group by in LINQ
Let's suppose if we have a class like:
10 Answers
10
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pull out p-values and r-squared from a linear regression
How do you pull out the p-value (for the significance of the coefficient of the single explanatory variable being non-zero) and R-squared value from a simple linear regression model? For example...
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Custom CSS Scrollbar for Firefox
... is now limited customization available in Firefox!
See these answers:
https://stackoverflow.com/a/54101063/405015
https://stackoverflow.com/a/53739309/405015
And this for background info: https://bugzilla.mozilla.org/show_bug.cgi?id=1460109
There's no Firefox equivalent to ::-webkit-scrollbar an...
Principal component analysis in Python
I'd like to use principal component analysis (PCA) for dimensionality reduction. Does numpy or scipy already have it, or do I have to roll my own using numpy.linalg.eigh ?
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Permutations in JavaScript?
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If you notice, the code actually splits the chars into an array prior to do any permutation, so you simply remove the join and split operation
var permArr = [],
usedChars = [];
function permute(input) {
var i, ch;
for (i = 0; i < input.len...