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What exactly is nullptr?
We now have C++11 with many new features. An interesting and confusing one (at least for me) is the new nullptr .
14 Answe...
Long list of if statements in Java
Sorry I can't find a question answering this, I'm almost certain someone else has raised it before.
15 Answers
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Create a branch in Git from another branch
I have two branches: master and dev
9 Answers
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conditional unique constraint
I have a situation where i need to enforce a unique constraint on a set of columns, but only for one value of a column.
6 A...
Java SafeVarargs annotation, does a standard or best practice exist?
I've recently come across the java @SafeVarargs annotation. Googling for what makes a variadic function in Java unsafe left me rather confused (heap poisoning? erased types?), so I'd like to know a few things:
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Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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Is optimisation level -O3 dangerous in g++?
I have heard from various sources (though mostly from a colleague of mine), that compiling with an optimisation level of -O3 in g++ is somehow 'dangerous', and should be avoided in general unless proven to be necessary.
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Why is there no Constant feature in Java?
I was trying to identify the reason behind constants in Java
I have learned that Java allows us to declare constants by using final keyword.
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Algorithm to return all combinations of k elements from n
I want to write a function that takes an array of letters as an argument and a number of those letters to select.
71 Answe...
Java 8 Streams - collect vs reduce
When would you use collect() vs reduce() ? Does anyone have good, concrete examples of when it's definitely better to go one way or the other?
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