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Is log(n!) = Θ(n·log(n))?
...og(n - 1) + log(n) (larger half of the terms of log(n!)). Actually, I just read the question and saw that the clue is stated in the question. Basically, (n/2)^(n/2) <= n! <= n^n => log((n/2)^(n/2))<=log(n!)<=log(n^n) => Θ(n/2 * log(n/2))<=log(n!)<=Θ(n*log(n))
...
C# binary literals
...es in terms of other values in the same class, and you have a very easy-to-read declarative syntax for bit flag enums.
[Flags]
enum Days
{
None = 0,
Sunday = 1,
Monday = 1 << 1, // 2
Tuesday = 1 << 2, // 4
Wednesday = 1 << 3, // 8
...
Android requires compiler compliance level 5.0 or 6.0. Found '1.7' instead. Please use Android Tools
... project folder and right click on it -> properties -> check off the read only box and click ok
Right-click on your project and select "Android Tools -> Fix Project Properties"
Right-click on your project and select "Properties -> Java Compiler", check "Enable project specific settings"...
How to debug .htaccess RewriteRule not working
...u have an idea of when does the .htaccess file load? I though apache would read this first
– macha
Feb 10 '12 at 20:31
...
When does invoking a member function on a null instance result in undefined behavior?
...tanding, if p were a hardware address which would trigger some action when read, but were not declared volatile, the statement *p; would not be required, but would be allowed, to actually read that address; the statement &(*p);, however, would be forbidden from doing so. If *p were volatile, th...
How do 20 questions AI algorithms work?
...
I recommend reading about the game here: http://en.wikipedia.org/wiki/Twenty_Questions
In particular the Computers section:
The game suggests that the information
(as measured by Shannon's entropy
statistic) required to identif...
pandas DataFrame: replace nan values with average of columns
...
# To read data from csv file
Dataset = pd.read_csv('Data.csv')
X = Dataset.iloc[:, :-1].values
# To calculate mean use imputer class
from sklearn.impute import SimpleImputer
imputer = SimpleImputer(missing_values=np.nan, strateg...
Can you have multiple $(document).ready(function(){ … }); sections?
... neatest thing to do. Try not to overuse them, as it will seriously affect readability. Other than that , it's perfectly legal. See the below:
http://www.learningjquery.com/2006/09/multiple-document-ready
Try this out:
$(document).ready(function() {
alert('Hello Tom!');
});
$(document).ready...
When to use next() and return next() in Node.js
...);
// do something
});
It saves me an indentation level, and when I read the code again later, I'm sure there is no way next is called twice.
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How to find keys of a hash?
...
# OUTPUT
# > a 1
# > b 2
# > ["a", "b"]
However, since ECMA5 already added Object.keys you might as well use:
Object.defineProperty(Object.prototype, 'keys', {
value: function keys() {
return Object.keys(this);
},
enumerable: false
});
Original answer
Object.prototype.keys ...