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Time complexity of Sieve of Eratosthenes algorithm
...oose upper-bound is n(1+1/2+1/3+1/4+1/5+1/6+…1/n) (sum of reciprocals of all numbers up to n), which is O(n log n): see Harmonic number. A more proper upper-bound is n(1/2 + 1/3 + 1/5 + 1/7 + …), that is sum of reciprocals of primes up to n, which is O(n log log n). (See here or here.)
The "find...
Merge a Branch into Trunk
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Really? Without risking remerging the same changesets? Can you provide a link to corroborating evidence of this please.
– Neutrino
Apr 3 '12 at 16:56
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How to use mongoimport to import csv
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Is it possible to import all the records from the csv into just 1 object instead of 1 object per record?
– Aniket Kapse
Aug 22 '16 at 12:34
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Changing a specific column name in pandas DataFrame
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A one liner does exist:
In [27]: df=df.rename(columns = {'two':'new_name'})
In [28]: df
Out[28]:
one three new_name
0 1 a 9
1 2 b 8
2 3 c 7
3 4 d 6
4 5 e 5
Following is the docstring for the rename method.
De...
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
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Any way to replace characters on Swift String?
...n leaves me with and optional string. Original String looks like this: "x86_64" and the new mapping looks like "Optional([\"x\", \"8\", \"6\", \"_\", \"6\", \"4\"])"
– John Shelley
Oct 19 '15 at 15:07
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How do I execute a command and get the output of the command within C++ using POSIX?
...use the C stdio API, I prefer the iostreams API. popen requires you to manually clean up the FILE handle, pstreams do that automatically. popen only accepts a const char* for the argument, which requires care to avoid shell injection attacks, pstreams allows you to pass a vector of strings similar t...
How to assign from a function which returns more than one value?
...eturningTwoValues()
If you only need the first or second component these all work too:
list[a] <- functionReturningTwoValues()
list[a, ] <- functionReturningTwoValues()
list[, b] <- functionReturningTwoValues()
(Of course, if you only needed one value then functionReturningTwoValues()[...
Advantages to Using Private Static Methods
When creating a class that has internal private methods, usually to reduce code duplication, that don't require the use of any instance fields, are there performance or memory advantages to declaring the method as static?
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passport.js passport.initialize() middleware not in use
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I keep getting this exception after authentication success (I see the callback url on the browser):
7 Answers
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