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map vs. hash_map in C++
...tied to that key.
map is implemented as a balanced binary search tree (usually a red/black tree).
An unordered_map should give slightly better performance for accessing known elements of the collection, but a map will have additional useful characteristics (e.g. it is stored in sorted order, which...
Rename MySQL database [duplicate]
...atabase with the database name you wanted.
The short, quick steps without all the above explanation are:
mysqldump -u root -p original_database > original_database.sql
mysql -u root -p -e "create database my_new_database"
mysql -u root -p my_new_database < original_database.sql
mysql -u roo...
Core dumped, but core file is not in the current directory?
...fied 14.04), there's an easy temporary workaround for this by running sudo service apport stop --- after I ran that, it changed /proc/sys/kernel/core_pattern from the apport pipe to just core. Apport is smart enough to fix up the core_pattern temporarily, I suppose.
– Patrick C...
Access an arbitrary element in a dictionary in Python
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for a non-destructive popitem you can make a (shallow) copy: key, value = dict(d).popitem()
– Pelle
Jan 31 '18 at 10:35
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Random String Generator Returning Same String [duplicate]
...om instance in the method, which causes it to return the same values when called in quick succession. I would do something like this:
private static Random random = new Random((int)DateTime.Now.Ticks);//thanks to McAden
private string RandomString(int size)
{
StringBuilder builder = new...
Difference between “managed” and “unmanaged”
...ns on the CLR (Common Language Runtime), which, among other things, offers services like garbage collection, run-time type checking, and reference checking. So, think of it as, "My code is managed by the CLR."
Visual Basic and C# can only produce managed code, so, if you're writing an application i...
What's the proper way to install pip, virtualenv, and distribute for Python?
...estion 4314376 , I recommended using ez_setup so that you could then install pip and virtualenv as follows:
15 Answer...
What is the most robust way to force a UIView to redraw?
...ouble with that, you're likely running into one of these issues:
You're calling it before you actually have the data, or your -drawRect: is over-caching something.
You're expecting the view to draw at the moment you call this method. There is intentionally no way to demand "draw right now this ver...
How to set environment variables in Jenkins?
...ajorVersion" | python -c 'import sys,re,os; print("VERSION_NUMBER="+re.findall(r"[\d+\.]+", sys.stdin.read())[0]+os.environ["BUILD_NUMBER"])'
– kenny_k
Jun 19 '15 at 6:52
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Android Get Current timestamp?
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From developers blog:
System.currentTimeMillis() is the standard "wall" clock (time and date) expressing milliseconds since the epoch. The wall clock can be set by the user or the phone network (see setCurrentTimeMillis(long)), so the time may jump backwards or forwards unpredictably. This c...