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Convert a list of characters into a string
If I have a list of chars:
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Can you explain the concept of streams?
I understand that a stream is a representation of a sequence of bytes. Each stream provides means for reading and writing bytes to its given backing store. But what is the point of the stream? Why isn't the backing store itself what we interact with?
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Should I use PATCH or PUT in my REST API?
I want to design my rest endpoint with the appropriate method for the following scenario.
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Extracting specific columns from a data frame
I have an R data frame with 6 columns, and I want to create a new dataframe that only has three of the columns.
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Algorithm for creating a school timetable
I've been wondering if there are known solutions for algorithm of creating a school timetable. Basically, it's about optimizing "hour-dispersion" (both in teachers and classes case) for given class-subject-teacher associations. We can assume that we have sets of classes, lesson subjects and teacher...
Convert RGB to RGBA over white
I have a hex color, e.g. #F4F8FB (or rgb(244, 248, 251) ) that I want converted into an as-transparent-as-possible rgba color (when displayed over white). Make sense? I'm looking for an algorithm, or at least idea of an algorithm for how to do so.
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Is recursion ever faster than looping?
I know that recursion is sometimes a lot cleaner than looping, and I'm not asking anything about when I should use recursion over iteration, I know there are lots of questions about that already.
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Running PostgreSQL in memory only
I want to run a small PostgreSQL database which runs in memory only, for each unit test I write. For instance:
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Count the number occurrences of a character in a string
What's the simplest way to count the number of occurrences of a character in a string?
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Why does C++ not allow inherited friendship?
Why is friendship not at least optionally inheritable in C++? I understand transitivity and reflexivity being forbidden for obvious reasons (I say this only to head off simple FAQ quote answers), but the lack of something along the lines of virtual friend class Foo; puzzles me. Does anyone know ...