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How to prove that a problem is NP complete?
...least one vertex in the cover set?) is in NP:
our input X is some graph G and some number k (this is from the problem definition)
Take our information C to be "any possible subset of vertices in graph G of size k"
Then we can write an algorithm V that, given G, k and C, will return whether that s...
In Python, using argparse, allow only positive integers
...
type would be the recommended option to handle conditions/checks, as in Yuushi's answer.
In your specific case, you can also use the choices parameter if your upper limit is also known:
parser.add_argument('foo', type=int, choices=xrange(5, 10))
Note: Use range ...
How can I select multiple columns from a subquery (in SQL Server) that should have one record (selec
...es from the row with the highest value for Foo (rather than the max of Foo and the max of Foo2 - which is NOT the same thing) then the following will usually work better than a subquery:
SELECT
A.SalesOrderID,
A.OrderDate,
B1.Foo,
B1.Foo2
FROM
A
LEFT OUTER JOIN B AS B1 ON
...
Map.clear() vs new Map : Which one will be better? [duplicate]
...h is backed with new array. So, garbage collector should clear all the key and values from the previous map, and clear the reference to itself. So O(n) algorithm is executed anyway, but in the garbage collector thread. For 1000 records you won't see any difference.
BUT. The performance guide tells ...
How to implement infinity in Java?
...X_VALUE field of the Integer class:
Integer myInf = Integer.MAX_VALUE;
(And for NEGATIVE_INFINITY you could use MIN_VALUE.) There will of course be some functional differences, e.g., when comparing myInf to a value that happens to be MAX_VALUE: clearly this number isn't less than myInf.
There's ...
python pandas: apply a function with arguments to a series
I want to apply a function with arguments to a series in python pandas:
4 Answers
4
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Animate text change in UILabel
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I wonder if it works, and it works perfectly!
Objective-C
[UIView transitionWithView:self.label
duration:0.25f
options:UIViewAnimationOptionTransitionCrossDissolve
animations:^{
self.l...
OpenSSL: PEM routines:PEM_read_bio:no start line:pem_lib.c:703:Expecting: TRUSTED CERTIFICATE [close
...ing in Stunnel's CApath directory. I have got some certs in this directory and they are working well. Also, I have a server sert and server key:
...
How do I get the real .height() of a overflow: hidden or overflow: scroll div?
...ave a question regarding how to get a div height. I'm aware of .height() and innerHeight() , but none of them does the job for me in this case. The thing is that in this case I have a div that is overflown width a overflow: scroll and the div has a fixed height.
...
Date query with ISODate in mongodb doesn't seem to work
...
Although $date is a part of MongoDB Extended JSON and that's what you get as default with mongoexport I don't think you can really use it as a part of the query.
If try exact search with $date like below:
db.foo.find({dt: {"$date": "2012-01-01T15:00:00.000Z"}})
you'll g...