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How to efficiently compare two unordered lists (not sets) in Python?
... Hey @Raymond, I recently encountered this question on an interview and I used sorted(), admittedly not knowing about Counter. The interviewer insisted there was a more efficient method and clearly I drew a blank. After extensive testing in python 3 with the timeit module, sorted consisten...
What is the difference between the add and offer methods in a Queue in Java?
... element can not be added to collection the add method throws an exception and offer doesn't.
From: http://java.sun.com/j2se/1.5.0/docs/api/java/util/Collection.html#add%28E%29
If a collection refuses to add a
particular element for any reason
other than that it already contains
the eleme...
How to use NSJSONSerialization
..."id": "2", "name":"Bbb"}]
This might give you a clear picture of how to handle it:
NSError *e = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutableContainers error: &e];
if (!jsonArray) {
NSLog(@"Error parsing JSON: %@", e);
} else {
for...
Have a div cling to top of screen if scrolled down past it [duplicate]
...has scrolled past it.
This is done with something like this, attaching a handler to the window.scroll event
// Cache selectors outside callback for performance.
var $window = $(window),
$stickyEl = $('#the-sticky-div'),
elTop = $stickyEl.offset().top;
$window.scroll(functi...
Are Swift variables atomic?
In Objective-C you have a distinction between atomic and nonatomic properties:
6 Answers
...
How to download an entire directory and subdirectories using wget?
...ect using wget , as the SVN server for that project isn't running anymore and I am only able to access the files through a browser. The base URLs for all the files is the same like
...
throw new std::exception vs throw std::exception
...
The conventional way to throw and catch exceptions is to throw an exception object and to catch it by reference (usually const reference). The C++ language requires the compiler to generate the appropriate code to construct the exception object and to pro...
How can I install Apache Ant on Mac OS X?
I tried to install Apache Ant on my Mac and I followed the next steps :
8 Answers
8
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In javascript, is an empty string always false as a boolean?
...
Yes. Javascript is a dialect of ECMAScript, and ECMAScript language specification clearly defines this behavior:
ToBoolean
The result is false if the argument is the empty String (its length is zero);
otherwise the result is true
Quote taken from http://www.ecma-inte...
GDB corrupted stack frame - How to debug?
...
Those bogus adresses (0x00000002 and the like) are actually PC values, not SP values. Now, when you get this kind of SEGV, with a bogus (very small) PC address, 99% of the time it's due to calling through a bogus function pointer. Note that virtual calls i...
