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Permutations in JavaScript?

...lementation to the following benchmark.js test suite: function permute_SiGanteng(input) { var permArr = [], usedChars = []; function permute(input) { var i, ch; for (i = 0; i < input.length; i++) { ch = input.splice(i, 1)[0]; usedChars.push(ch); if...
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Calculate distance between 2 GPS coordinates

...y solution: #include <math.h> #include "haversine.h" #define d2r (M_PI / 180.0) //calculate haversine distance for linear distance double haversine_km(double lat1, double long1, double lat2, double long2) { double dlong = (long2 - long1) * d2r; double dlat = (lat2 - lat1) * d2r; ...
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Looping through a hash, or using an array in PowerShell

... how: $hash = @{ a = 1 b = 2 c = 3 } $hash.Keys | % { "key = $_ , value = " + $hash.Item($_) } Output: key = c , value = 3 key = a , value = 1 key = b , value = 2 share | improve th...
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Nested defaultdict of defaultdict

... For an arbitrary number of levels: def rec_dd(): return defaultdict(rec_dd) >>> x = rec_dd() >>> x['a']['b']['c']['d'] defaultdict(<function rec_dd at 0x7f0dcef81500>, {}) >>> print json.dumps(x) {"a": {"b": {"c": {"d": {}}}}} ...
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How to shuffle a std::vector?

...#include <algorithm> #include <random> auto rng = std::default_random_engine {}; std::shuffle(std::begin(cards_), std::end(cards_), rng); Live example on Coliru Make sure to reuse the same instance of rng throughout multiple calls to std::shuffle if you intend to generate different p...
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MongoDB SELECT COUNT GROUP BY

...ier way to do it using aggregate: db.contest.aggregate([ {"$group" : {_id:"$province", count:{$sum:1}}} ]) share | improve this answer | follow | ...
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Linux command or script counting duplicated lines in a text file?

...3 } or you can use a simple one-liner: $ cat filename | python3 -c 'print(__import__("json").dumps(__import__("collections").Counter(map(str.strip, __import__("fileinput").input())), indent=2))' share | ...
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How can I expand the full path of the current file to pass to a command in Vim?

...ught me here, this should be the chosen answer. – doc_id Mar 2 '13 at 1:15 add a comment  |  ...
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php $_POST array empty upon form submission

...ed to share it as it cost me much time. When using JSON content-type the $_POST array will not populate (only with multi-part forms I believe) Here is what did work to correct the issue: $rest_json = file_get_contents("php://input"); $_POST = json_decode($rest_json, true); hope this helps someo...
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Updating MySQL primary key

I have a table user_interactions with 4 columns: 3 Answers 3 ...