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What is pseudopolynomial time? How does it differ from polynomial time?
...ng TSP takes time O(n · n!), which isn't polynomial time.
These runtimes all refer to some variable n that tracks the size of the input. For example, in selection sort, n refers to the number of elements in the array, while in TSP n refers to the number of nodes in the graph. In order to standardi...
Unique BooleanField value in Django?
... save method of the model and if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
...
Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes
...and updating the model values (EditableValueHolder components only) and finally invoke the queued ActionEvent (ActionSource components only). JSF will skip processing of all other components which are not covered by process attribute. Also, components whose rendered attribute evaluates to false duri...
Vim: Creating parent directories on save
...ries for files like ftp://* and !isdirectory will prevent expensive mkdir call.
Update: sligtly better solution that also checks for non-empty buftype and uses mkdir():
function s:MkNonExDir(file, buf)
if empty(getbufvar(a:buf, '&buftype')) && a:file!~#'\v^\w+\:\/'
let dir=...
Naming convention for Scala constants?
...
The officially recommended style (and I do mean officially) is the first style, camel case with first letter are upper case. It's laid down clearly by Odersky on Programming in Scala.
The style is also followed by the standard library...
Is it better to call ToList() or ToArray() in LINQ queries?
...the case where I want to eval a query right where I declare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
...
Error 908: Permission Receive SMS - #5 by Taifun - MIT App Inventor Help - MIT App Inventor Community
...in points from that thread here
Google Play Store policy requires that all apps declaring the ability to send text and make phone calls directly without user intervention, or to receive texts and phone calls, require a manual review by Google staff. The MIT App Inventor Companion was one such ...
Should I use int or Int32
...
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For those of you with the old C++ mindset, IntPtr is designed to be 32 bits on a 32 bit OS and 64 bits on a 64 bit OS. This behavior is spe...
How can I handle R CMD check “no visible binding for global variable” notes when my ggplot2 syntax i
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Just another warning. aes_string does not allow you to use functions to manipulate the x and y values. Say that you would like to log transform y in which case aes_string(x = 'x.values', y='log(y.values)') of course doesn't work. I use these kind of transformations a...
What is difference between Collection.stream().forEach() and Collection.forEach()?
...at with .stream() , I can use chain operations like .filter() or use parallel stream. But what is difference between them if I need to execute small operations (for example, printing the elements of the list)?
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