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How to copy a dictionary and only edit the copy
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It might be better to say "dict2 and dict1 point to the same dictionary", you are not changing dict1 or dict2 but what they point to.
– GrayWizardx
Mar 17 '10 at 21:15
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Multiple arguments to function called by pthread_create()?
...way to do this is to define a struct, pass the function a pointer to that, and dereference it for the arguments. However, I am unable to get this to work:
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unix - head AND tail of file
Say you have a txt file, what is the command to view the top 10 lines and bottom 10 lines of file simultaneously?
20 Answer...
How to reverse a singly linked list using only two pointers?
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Any alternative? No, this is as simple as it gets, and there's no fundamentally-different way of doing it. This algorithm is already O(n) time, and you can't get any faster than that, as you must modify every node.
It looks like your code is on the right track, but it's not...
How to select the rows with maximum values in each group with dplyr? [duplicate]
...oup_by(A, B) %>% top_n(n=1)
This will rank by the last column (value) and return the top n=1 rows.
Currently, you can't change the this default without causing an error (See https://github.com/hadley/dplyr/issues/426)
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In Python, how do I create a string of n characters in one line of code?
...e same letter 10 times:
string_val = "x" * 10 # gives you "xxxxxxxxxx"
And if you want something more complex, like n random lowercase letters, it's still only one line of code (not counting the import statements and defining n):
from random import choice
from string import ascii_lowercase
n = ...
Why does Popen.communicate() return b'hi\n' instead of 'hi'?
...someone explain why the result I want, "hi", is preceded with a letter 'b' and followed with a newline?
4 Answers
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Hidden features of Scala
...e second line looks confusing if you're not used to using pattern matching and extractors. Whenever you define a val or var, what comes after the keyword is not simply an identifier but rather a pattern. That's why this works:
val (a, b, c) = (1, 3.14159, "Hello, world")
The right hand expressi...
How to drop SQL default constraint without knowing its name?
...ver, I know the query to check if a default constraint exists for a column and drop a default constraint is:
14 Answers
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String.Join method that ignores empty strings?
... I'm getting an error: "'Where' is not a member of 'System.Array'". And I don't see anything about 'Where' on MSDN: msdn.microsoft.com/en-us/library/system.array.aspx
– Doug
May 2 '13 at 12:55
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