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Why prefer two's complement over sign-and-magnitude for signed numbers?
...o add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
0001 is 1, which is the expected result of "2+(-1)".
But in your "intuitive" method, adding is m...
How do I perform the SQL Join equivalent in MongoDB?
...rect. The new $lookup operator added to the aggregation pipeline is essentially identical to a left outer join:
https://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <...
What is the largest TCP/IP network port number allowable for IPv4?
...wever ports are divided into:
Well-known ports: 0 to 1023 (used for system services e.g. HTTP, FTP, SSH, DHCP ...)
Registered/user ports: 1024 to 49151 (you can use it for your server, but be careful some famous applications: like Microsoft SQL Server database management system (MSSQL) server or Apa...
Dynamically set local variable [duplicate]
How do you dynamically set local variable in Python (where the variable name is dynamic)?
7 Answers
...
How to implement __iter__(self) for a container object (Python)
...
I normally would use a generator function. Each time you use a yield statement, it will add an item to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
...
How exactly does __attribute__((constructor)) work?
...
It runs when a shared library is loaded, typically during program startup.
That's how all GCC attributes are; presumably to distinguish them from function calls.
GCC-specific syntax.
Yes, this works in C and C++.
No, the function does not need to be static.
The destructo...
Open application after clicking on Notification
... notificationManager = (NotificationManager) context
.getSystemService(Context.NOTIFICATION_SERVICE);
Notification notification = new Notification(icon, message, when);
Intent notificationIntent = new Intent(context, HomeActivity.class);
notificationIntent.setFlags(Intent.F...
AngularJs: Reload page
...
You can use the reload method of the $route service. Inject $route in your controller and then create a method reloadRoute on your $scope.
$scope.reloadRoute = function() {
$route.reload();
}
Then you can use it on the link like this:
<a ng-click="reloadRoute...
Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
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How do I find out if the GPS of an Android device is enabled
...he following:
final LocationManager manager = (LocationManager) getSystemService( Context.LOCATION_SERVICE );
if ( !manager.isProviderEnabled( LocationManager.GPS_PROVIDER ) ) {
buildAlertMessageNoGps();
}
private void buildAlertMessageNoGps() {
final AlertDialog.Builder bu...