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Get nth character of a string in Swift programming language
...ng a linear loop inside another linear loop means this for loop is accidentally O(n2) — as the length of the string increases, the time this loop takes increases quadratically. Instead of doing that you could use the characters's string collection.
– ignaciohugog
...
Bad class file magic or version
...K section, when you add an Android SDK you should provide the Java SDK and all my Android SDKs uses Java 8 as SDK so it create the class files with the wrong version even if the Project level is 1.7 (i don't know why, i supposed that everything was choosed by Project level).
Now i changed the SDK (...
How to get an object's properties in JavaScript / jQuery?
...Script's native for in loop:
var obj = {
foo: 'bar',
base: 'ball'
};
for(var key in obj) {
alert('key: ' + key + '\n' + 'value: ' + obj[key]);
}
or using jQuery's .each() method:
$.each(obj, function(key, element) {
alert('key: ' + key + '\n' + 'value: ' + element);
});
W...
How to remove constraints from my MySQL table?
...
Postgres, MSSQL, and Oracle all have alter table .. drop constraint. MySQL is the odd one out, it seems.
– Jared Beck
Mar 23 '15 at 23:48
...
Redirecting Output from within Batch file
... good and fast way that only opens and positions the file once
@echo off
call :sub >output.txt
exit /b
:sub
command1
command2
...
commandN
Edit 2020-04-17
Every now and then you may want to repeatedly write to two or more files. You might also want different messages on the screen. It is sti...
How to detect if app is being built for device or simulator in Swift
... ...
#endif
After Swift 4.1 version
Latest use, now directly for all in one condition for all types of simulators need to apply only one condition -
#if targetEnvironment(simulator)
// your simulator code
#else
// your real device code
#endif
For more clarification, you can check S...
How can I access “static” class variables within class methods in Python?
...
As with all good examples, you've simplified what you're actually trying to do. This is good, but it is worth noting that python has a lot of flexibility when it comes to class versus instance variables. The same can be said of meth...
Can iterators be reset in Python?
...ary data needs to be
stored). In general, if one iterator
uses most or all of the data before
another iterator starts, it is faster
to use list() instead of tee().
Basically, tee is designed for those situation where two (or more) clones of one iterator, while "getting out of sync" with ea...
How to automatically remove trailing whitespace in Visual Studio 2008?
Is it possible to configure Visual Studio 2008 to automatically remove whitespace characters at the end of each line when saving a file? There doesn't seem to be a built-in option, so are there any extensions available to do this?
...
C++ performance vs. Java/C#
...p of a virtual machine which abstracts away the native architecture. Logically it would seem impossible for Java or C# to match the speed of C++ because of this intermediate step, however I've been told that the latest compilers ("hot spot") can attain this speed or even exceed it.
...