大约有 40,000 项符合查询结果（耗时：0.0445秒） [XML]
[科普] __MACOSX是什么文件夹？ - 更多技术 - 清泛网 - 专注C/C++及内核技术
...者就可以把这个压缩包上传到网上供人下载。但是有一个问题，苹果公司和其它的大的软件公司一样，十分擅长曲解和附会用户的意思，它很多时候并不是完全按照你的意思去做的。例如在这种情况下，你以为Mac仅仅是把你想要...
When to use enumerateObjectsUsingBlock vs. for
...
Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fas...
Why is there huge performance hit in 2048x2048 versus 2047x2047 array multiplication?
...he misses on matice1 are not the problem because they are accessed sequentially.
However for matice2 if a full column fits in L2 (i.e when you access matice2[0, 0], matice2[1, 0], matice2[2, 0] ... etc, nothing gets evicted) than there is no problem with cache misses with matice2 either.
Now to go ...
Why is IntelliJ 13 IDEA so slow after upgrading from version 12?
While using IntelliJ 13 ultimate edition for a week, it just seems really slow.
20 Answers
...
Why must wait() always be in synchronized block
We all know that in order to invoke Object.wait() , this call must be placed in synchronized block, otherwise an IllegalMonitorStateException is thrown. But what's the reason for making this restriction? I know that wait() releases the monitor, but why do we need to explicitly acquire the mon...
Select n random rows from SQL Server table
...the key scan of values plus the join cost, which on a large table with a small percentage selection should be reasonable.
share
|
improve this answer
|
follow
...
What is the most ridiculous pessimization you've seen? [closed]
We all know that premature optimization is the root of all evil because it leads to unreadable/unmaintainable code. Even worse is pessimization, when someone implements an "optimization" because they think it will be faster, but it ends up being slower, as well as being buggy, unmaintainable, etc...
What is “thread local storage” in Python, and why do I need it?
In Python specifically, how do variables get shared between threads?
5 Answers
5
...
Divide a number by 3 without using *, /, +, -, % operators
...n which performs the desired operation. But it requires the + operator, so all you have left to do is to add the values with bit-operators:
// replaces the + operator
int add(int x, int y)
{
while (x) {
int t = (x & y) << 1;
y ^= x;
x = t;
}
return y;
}...
Remove spaces from std::string in C++
... preferred way to remove spaces from a string in C++? I could loop through all the characters and build a new string, but is there a better way?
...