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Get operating system info
...t 10/i' => 'Windows 10',
'/windows nt 6.3/i' => 'Windows 8.1',
'/windows nt 6.2/i' => 'Windows 8',
'/windows nt 6.1/i' => 'Windows 7',
'/windows nt 6.0/i' =>...
Memoization in Haskell?
...
f mf 0 = 0
f mf n = max n $ mf (n `div` 2) +
mf (n `div` 3) +
mf (n `div` 4)
You can get an unmemoized f by using fix f
This will let you test that f does what you mean for small values of f by calling, for example: fix f 123 = 144
We could memoize this by def...
Rotating a two-dimensional array in Python
...ider the following two-dimensional list:
original = [[1, 2],
[3, 4]]
Lets break it down step by step:
>>> original[::-1] # elements of original are reversed
[[3, 4], [1, 2]]
This list is passed into zip() using argument unpacking, so the zip call ends up being the equiva...
How to print a number with commas as thousands separators in JavaScript
...h commas as thousands separators. For example, I want to show the number 1234567 as "1,234,567". How would I go about doing this?
...
Markdown: continue numbered list
In the following markdown code I want item 3 to start with list number 3. But because of the code block in between markdown starts this list item as a new list. Is there any way to prevent that behaviour?
...
How to iterate a loop with index and element in Swift
...
Yes. As of Swift 3.0, if you need the index for each element along with its value, you can use the enumerated() method to iterate over the array. It returns a sequence of pairs composed of the index and the value for each item in the array. F...
Can you delete multiple branches in one command with Git?
...lean up my local repository, which has a ton of old branches: for example 3.2 , 3.2.1 , 3.2.2 , etc.
29 Answers
...
Python assigning multiple variables to same value? list behavior
...es are naming the same object, use the is operator:
>>> a=b=c=[0,3,5]
>>> a is b
True
You then ask:
what is different from this?
d=e=f=3
e=4
print('f:',f)
print('e:',e)
Here, you're rebinding the name e to the value 4. That doesn't affect the names d and f in any way.
...
Getting SyntaxError for print with keyword argument end=' '
...
Are you sure you are using Python 3.x? The syntax isn't available in Python 2.x because print is still a statement.
print("foo" % bar, end=" ")
in Python 2.x is identical to
print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to...
Python Dictionary Comprehension
...t; d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set multiple ke...