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For i = 0, why is (i += i++) equal to 0?
...ation):
int i = 0;
i = i + i; // i=0 because the ++ is a postfix operator and hasn't been executed
i + 1; // Note that you are discarding the calculation result
What actually happens is more involved than that - take a look at MSDN, 7.5.9 Postfix increment and decrement operators:
The run-tim...
How do I clone a single branch in Git?
...g a shallow clone.
This makes git clone --depth 1 the easiest way to save bandwidth.
And since Git 1.9.0 (February 2014), shallow clones support data transfer (push/pull), so that option is even more useful now.
See more at "Is git clone --depth 1 (shallow clone) more useful than it makes out?".
"...
Piping both stdout and stderr in bash?
...t newer versions of bash have the &> operator, which (if I understand correctly), redirects both stdout and stderr to a file ( &>> appends to the file instead, as Adrian clarified).
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How to create .ipa file using Xcode?
...lick Product > Archive > once this is complete open up the Organiser and click the latest version.
Step 3:
Click on Export... option from right side of organiser window.
Step 4:
Select a method for export > Choose correct signing > Save to Destination.
Xcode 10.0
Step 3:
From R...
Algorithm to generate all possible permutations of a list?
... left to right, all the permutations of the remaining items are generated (and each one is added with the current elements). This can be done recursively (or iteratively if you like pain) until the last item is reached at which point there is only one possible order.
So with the list [1,2,3,4] all ...
Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]
...y ways to do this. This answer starts with what is quickly becoming the standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site.
tmp <- data.frame(x=gl(2,3, labels=letters[24:25]),
y=gl(3,1,6, labe...
Why does direction of index matter in MongoDB?
...
MongoDB concatenates the compound key in some way and uses it as the key in a BTree.
When finding single items - The order of the nodes in the tree is irrelevant.
If you are returning a range of nodes - The elements close to each other will be down the same branches of th...
nonlocal keyword in Python 2.x
I'm trying to implement a closure in Python 2.6 and I need to access a nonlocal variable but it seems like this keyword is not available in python 2.x. How should one access nonlocal variables in closures in these versions of python?
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How do I prompt for Yes/No/Cancel input in a Linux shell script?
I want to pause input in a shell script, and prompt the user for choices.
The standard Yes , No , or Cancel type question.
How do I accomplish this in a typical bash prompt?
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How to remove elements from a generic list while iterating over it?
...er pattern for working with a list of elements which each need processed and then depending on the outcome are removed from the list.
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