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How does Java handle integer underflows and overflows and how would you check for it?
How does Java handle integer underflows and overflows?
12 Answers
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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...
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...
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 ...
How do I create a readable diff of two spreadsheets using git diff?
...ode repository. These are usually edited with gnumeric or openoffice.org, and are mostly used to populate databases for unit testing with dbUnit . There are no easy ways of doing diffs on xls files that I know of, and this makes merging extremely tedious and error prone.
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How can I do a line break (line continuation) in Python?
...g line of code that I want to break up among multiple lines. What do I use and what is the syntax?
10 Answers
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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?".
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Good tutorials on XMPP? [closed]
I've been looking at some open-source XMPP servers, and am familiar with the official page http://xmpp.org/ . But thus far I've not found anything in between " The Extensible Messaging and Presence Protocol (XMPP) is an open technology for real-time communication " and a list of XEP specifications....
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 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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