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Why use def main()? [duplicate]
...ink I still have something else to add.
Reasons to have that if statement calling main() (in no particular order):
Other languages (like C and Java) have a main() function that is called when the program is executed. Using this if, we can make Python behave like them, which feels more familiar for ...
How to get the client IP address in PHP [duplicate]
...se addresses are larger than the older IPv4 addresses.
(Note that IPv6 usually uses 39 characters at most but there is also a special IPv6 notation for IPv4 addresses which in its full form can be up to 45 characters. So if you know what you are doing you can use 39 characters, but if you just want...
String concatenation in Ruby
...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil.
When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator.
In the end, it is a matter of taste....
Asynchronous method call in Python?
I was wondering if there's any library for asynchronous method calls in Python . It would be great if you could do something like
...
What is the difference between a field and a property?
...sed via get and set properties. Properties provide a level of abstraction allowing you to change the fields while not affecting the external way they are accessed by the things that use your class.
public class MyClass
{
// this is a field. It is private to your class and stores the actual da...
How can I create a copy of an object in Python?
...would like to create a copy of an object. I want the new object to possess all properties of the old object (values of the fields). But I want to have independent objects. So, if I change values of the fields of the new object, the old object should not be affected by that.
...
Why doesn't list have safe “get” method like dictionary?
...accessing list elements (as the len method is very fast). The .get method allows you to query the value associated with a name, not directly access the 37th item in the dictionary (which would be more like what you're asking of your list).
Of course, you can easily implement this yourself:
def sa...
How to deal with SettingWithCopyWarning in Pandas?
...
The SettingWithCopyWarning was created to flag potentially confusing "chained" assignments, such as the following, which does not always work as expected, particularly when the first selection returns a copy. [see GH5390 and GH5597 for background discussion.]
df[df['A'] > 2...
Accessing Object Memory Address
When you call the object.__repr__() method in Python you get something like this back:
9 Answers
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How to implement a queue with three stacks?
...r Sedgewick have confirmed they are not aware of a 3-stack solution within all the constraints of the original question
DETAILS
There are two implementations behind this link: http://www.eecs.usma.edu/webs/people/okasaki/jfp95/index.html
One of them is O(1) with three stacks BUT it uses lazy exe...