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What is the exact problem with multiple inheritance?
...g part of the problem, if one does not need to allow identity-preserving upcasts and downcasts among all of the types from which an instance is derived or for which it is substitutable. Given X:B; Y:B; and Z:X,Y; assume someZ is an instance of Z. With virtual inheritance, (B)(X)someZ and (B)(Y)som...
How to reset Android Studio
I want to reset Android Studio 0.2.13 to the default state. That means reset all settings, remove all projects, all gradle files so that it would act like a fresh installation. What steps do I have to follow to achieve this?
...
How to fix 'android.os.NetworkOnMainThreadException'?
I got an error while running my Android project for RssReader.
59 Answers
59
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How to fix java.net.SocketException: Broken pipe?
...e commons http client to call url using post method to post the parameters and it is throwing the below error rarely.
10 A...
Should switch statements always contain a default clause?
...akes appropriate action for unhandled values, in case an invalid value was cast to the enum type. So this may work best for simple cases where you can return within the enum case rather than break.
enum SomeEnum
{
ENUM_1,
ENUM_2,
// More ENUM values may be added in future
};
int foo(So...
Rails 3 - can't install pg gem
...g= 'PATH_TO_YOUR_PG_CONFIG'
If you are not sure where your pg_config is, and assuming you are on Linux or Mac, you can run the following command:
which pg_config
Your pg-config can be in different locations depending on how you installed postgres.
...
Python glob multiple filetypes
....glob in python to get a list of multiple file types such as .txt, .mdown, and .markdown? Right now I have something like this:
...
Using bitwise OR 0 to floor a number
...
How does it work? Our theory was that using such an operator casts the
number to an integer, thus removing the fractional part
All bitwise operations except unsigned right shift, >>>, work on signed 32-bit integers. So using bitwise operations will convert a float to an in...
Difference between shadowing and overriding in C#?
...Foo()); // output 1
Console.WriteLine(clB.Bar()); // output 1
//now let's cast B to an A class
Console.WriteLine(((A)clB).Foo()); // output 5 <<<-- shadow
Console.WriteLine(((A)clB).Bar()); // output 1
Suppose you have a base class and you use the base class in all your code instead of t...
Programmatically find the number of cores on a machine
...;sysinfo);
int numCPU = sysinfo.dwNumberOfProcessors;
Linux, Solaris, AIX and Mac OS X >=10.4 (i.e. Tiger onwards)
int numCPU = sysconf(_SC_NPROCESSORS_ONLN);
FreeBSD, MacOS X, NetBSD, OpenBSD, etc.
int mib[4];
int numCPU;
std::size_t len = sizeof(numCPU);
/* set the mib for hw.ncpu */
mib[...