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How to make an array of arrays in Java
Hypothetically, I have 5 string array objects:
4 Answers
4
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When is assembly faster than C?
...hat although that's not entirely false, the cases where assembler can actually be used to generate more performant code are both extremely rare and require expert knowledge of and experience with assembly.
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Can someone explain __all__ in Python?
I have been using Python more and more, and I keep seeing the variable __all__ set in different __init__.py files. Can someone explain what this does?
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What's the $unwind operator in MongoDB?
...hat it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you ...
Why is `std::move` named `std::move`?
The C++11 std::move(x) function doesn't really move anything at all. It is just a cast to r-value. Why was this done? Isn't this misleading?
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How to list branches that contain a given commit?
...uery git to find out which branches contain a given commit? gitk will usually list the branches, unless there are too many, in which case it just says "many (38)" or something like that. I need to know the full list, or at least whether certain branches contain the commit.
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What is the advantage of GCC's __builtin_expect in if else statements?
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I guess it should be something like:
cmp $x, 0
jne _foo
_bar:
call bar
...
jmp after_if
_foo:
call foo
...
after_if:
You can see that the instructions are arranged in such an order that the bar case precedes the foo case (as opposed to the C code). This can utilise the CPU ...
What is the difference between g++ and gcc?
... was once upon a time just the GNU C Compiler).
Even though they automatically determine which backends (cc1 cc1plus ...) to call depending on the file-type, unless overridden with -x language, they have some differences.
The probably most important difference in their defaults is which libraries ...
What's the difference between :: (double colon) and -> (arrow) in PHP?
... used to access static members, such usage is discouraged), while :: is usually used to access static members (though in a few special cases, it's used to access instance members).
In general, :: is used for scope resolution, and it may have either a class name, parent, self, or (in PHP 5.3) static...
If table exists drop table then create it, if it does not exist just create it
...s case than not to cover, see locking note below).
Second RENAME ... atomically replaces table definition, refer to
MySQL manual
for details.
At last, DROP ... just cleans up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...