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What is the preferred/idiomatic way to insert into a map?
...ons are not functionally equivalent :
The operator[] will search for the key, insert a default constructed value if not found, and return a reference to which you assign a value. Obviously, this can be inefficient if the mapped_type can benefit from being directly initialized instead of default co...
How do I find files that do not contain a given string pattern?
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ghostdog74ghostdog74
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How can I multiply and divide using only bit shifting and adding?
... and shifting you want to decompose one of the numbers by powers of two, like so:
21 * 5 = 10101_2 * 101_2 (Initial step)
= 10101_2 * (1 * 2^2 + 0 * 2^1 + 1 * 2^0)
= 10101_2 * 2^2 + 10101_2 * 2^0
= 10101_2 << 2 + 10101_2 << 0 (Decomposed)
= 1...
How to get random value out of an array?
...
You can also do just:
$k = array_rand($array);
$v = $array[$k];
This is the way to do it when you have an associative array.
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Evenly distributing n points on a sphere
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In this example code node[k] is just the kth node. You are generating an array N points and node[k] is the kth (from 0 to N-1). If that is all that is confusing you, hopefully you can use that now.
(in other words, k is an array of size N that is def...
How do I create an empty array/matrix in NumPy?
...del for using NumPy efficiently. NumPy arrays are stored in contiguous blocks of memory. If you want to add rows or columns to an existing array, the entire array needs to be copied to a new block of memory, creating gaps for the new elements to be stored. This is very inefficient if done repeatedly...
Get a pixel from HTML Canvas?
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Georg SchöllyGeorg Schölly
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Why is string concatenation faster than array join?
...S_NULL_OR_UNDEFINED(this) && !IS_UNDETECTABLE(this)) {
throw MakeTypeError("called_on_null_or_undefined", ["String.prototype.concat"]);
}
var len = %_ArgumentsLength();
var this_as_string = TO_STRING_INLINE(this);
if (len === 1) {
return this_as_string + %_Arguments(0);
}
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How to find and return a duplicate value in array
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a = ["A", "B", "C", "B", "A"]
a.detect{ |e| a.count(e) > 1 }
I know this isn't very elegant answer, but I love it. It's beautiful one liner code. And works perfectly fine unless you need to process huge data set.
Looking for faster solution? Here you go!
def find_one_using_hash_map(ar...
Index (zero based) must be greater than or equal to zero
Hey I keep getting an error:
8 Answers
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