大约有 14,000 项符合查询结果（耗时：0.0370秒） [XML]
Why does Java's hashCode() in String use 31 as a multiplier?
... subtract instruction. However, if your multiplier is slow this is still a win. Modern processors tend to have fast multipliers so it doesn't make much difference, so long as 32 goes on the correct side.
It's not a great hash algorithm, but it's good enough and better than the 1.0 code (and very mu...
\d is less efficient than [0-9]
... not [0-9].
You can generate a list of all such characters using the following code:
var sb = new StringBuilder();
for(UInt16 i = 0; i < UInt16.MaxValue; i++)
{
string str = Convert.ToChar(i).ToString();
if (Regex.IsMatch(str, @"\d"))
sb.Append(str);
}
Console.WriteLine(sb.ToStr...
Large Object Heap Fragmentation
...se allocated size is a multiple of 8 bytes would probably be a performance win. Otherwise, while performance of a heavily-used double[] that's cache-aligned would be better than that of one that isn't, I don't know why size would correlate with usage.
– supercat
...
What's the difference between a word and byte?
...ay abstracting these details.
Some APIs might confuse you though, such as Win32 API, because it has types such as WORD (16 bits) and DWORD (32 bits). The reason is that the API was initially targeting 16 bit machines, then was ported to 32 bit machines, then to 64 bit machines. To store a pointer, ...
Setting up a git remote origin
I have the following repos.
3 Answers
3
...
Simple example of threading in C++
...
Well, technically any such object will wind up being built over a C-style thread library because C++ only just specified a stock std::thread model in c++0x, which was just nailed down and hasn't yet been implemented. The problem is somewhat systemic, technically t...
Solutions for INSERT OR UPDATE on SQL Server
...
@CashCow, the last wins, this is what INSERT or UPDATE is supposed to do: the first one inserts, the second updates the record. Adding a lock allow this to happen in a very short time-frame, preventing an error.
– Jean Vin...
ruby inheritance vs mixins
...nd
end
class C
include A
include B
end
c = C.new
c.sayhi
Which one wins? In Ruby, it turns out the be the latter, module B, because you included it after module A. Now, it's easy to avoid this problem: make sure all of module A and module B's constants and methods are in unlikely namespace...
Collections.emptyMap() vs new HashMap()
...sing a Collection instead of null to avoid Exceptions being thrown on following operations? Using an immutable collection would just result in some other sort of exception I imagine. And assigning null is most certainly not less efficient than assigning a immutable constant.
– ...
CSS display: table min-height not working
...ks and min-height doesn't in Chrome 37, Safari 7 and FF 32 on mac. IE11 on Win 8.1 gives the correct behavior in both. jsfiddle.net/nuwcyvwn/1
– Stephan Muller
Sep 23 '14 at 11:54
...