大约有 6,000 项符合查询结果（耗时：0.0152秒） [XML]
How do malloc() and free() work?
...
OK some answers about malloc were already posted.
The more interesting part is how free works (and in this direction, malloc too can be understood better).
In many malloc/free implementations, free does normally not return the memory to the operating system (or at l...
Which is the preferred way to concatenate a string in Python?
... to a string, then to a list:
a += b:
0.10780501365661621
a.append(b):
0.1123361587524414
OK, turns out that even when the resulting string is a million characters long, appending was still faster.
Now let's try with appending a thousand character long string a hundred thousand times:
a += b:
0...
How to import other Python files?
...
There are many ways to import a python file, all with their pros and cons.
Don't just hastily pick the first import strategy that works for you or else you'll have to rewrite the codebase later on when you find it doesn't meet your needs.
I'll start out explaining the easiest exampl...
AngularJS $http and $resource
...hBen Lesh
104k4747 gold badges242242 silver badges231231 bronze badges
1
...
Dynamically set local variable [duplicate]
...ess the function locals through it:
>>> def foo():
... abc = 123
... lcl = zzz()
... lcl['abc'] = 456
... deF = 789
... print(abc)
... print(zzz())
... print(lcl)
...
>>> zzz =locals
>>> foo()
123
{'__doc__': None, '__builtins__': <module '_...
How to change line-ending settings
...
Line ending format used in OS
Windows: CR (Carriage Return \r) and LF (LineFeed \n) pair
OSX,Linux: LF (LineFeed \n)
We can configure git to auto-correct line ending formats for each OS in two ways.
Git Global configuration
Use .gitattributes file
...
What does Python's eval() do?
...ing and then have python run it as code. So for example: eval("__import__('os').remove('file')").
– BYS2
Feb 21 '12 at 19:24
...
How do I parse a string into a number with Dart?
...ing into an integer with int.parse(). For example:
var myInt = int.parse('12345');
assert(myInt is int);
print(myInt); // 12345
Note that int.parse() accepts 0x prefixed strings. Otherwise the input is treated as base-10.
You can parse a string into a double with double.parse(). For example:
va...
How to run a Python script in the background even after I logout SSH?
... process exits with status 1. What's going on?
– Santosh Ghimire
Dec 7 '13 at 15:03
1
read the ou...
Is there any difference between GROUP BY and DISTINCT
...ukas Eder
171k105105 gold badges562562 silver badges12371237 bronze badges
...