大约有 45,000 项符合查询结果（耗时：0.0554秒） [XML]
How do I exchange keys with values in a dictionary?
...
Python 2:
res = dict((v,k) for k,v in a.iteritems())
Python 3 (thanks to @erik):
res = dict((v,k) for k,v in a.items())
share
|
...
Maximum and Minimum values for ints
... the maximum value representable by an unsigned word will be sys.maxsize * 2 + 1, and the number of bits in a word will be math.log2(sys.maxsize * 2 + 2). See this answer for more information.
Python 2
In Python 2, the maximum value for plain int values is available as sys.maxint:
>>> sy...
Apache Prefork vs Worker MPM
...
120
Prefork and worker are two type of MPM apache provides. Both have their merits and demerits.
B...
Is “double hashing” a password less secure than just hashing it once?
...
270
Hashing a password once is insecure
No, multiple hashes are not less secure; they are an esse...
What's the difference between lapply and do.call?
...
127
There is a function called Map that may be similar to map in other languages:
lapply returns ...
Redirect all output to file [duplicate]
...
1213
That part is written to stderr, use 2> to redirect it. For example:
foo > stdout.txt 2&...
What are the GCC default include directories?
...
answered Jul 12 '11 at 15:01
Ihor KaharlichenkoIhor Kaharlichenko
4,80611 gold badge2323 silver badges2929 bronze badges
...
Accessing class variables from a list comprehension in the class definition
... comprehension within the class definition? The following works in Python 2 but fails in Python 3:
5 Answers
...
Python - Create list with numbers between 2 values?
...
Use range. In Python 2.x it returns a list so all you need is:
>>> range(11, 17)
[11, 12, 13, 14, 15, 16]
In Python 3.x range is a iterator. So, you need to convert it to a list:
>>> list(range(11, 17))
[11, 12, 13, 14, 15, ...
What are the mathematical/computational principles behind this game?
...into the soup and you have the question:
Can we have a geometry with just 2 points? With 3 points? With 4? With 7?
There are still open questions regarding this problem but we do know this:
If there are geometries with Q points, then Q = n^2 + n + 1 and n is called the order of the geometry.
The...