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Get nth character of a string in Swift programming language
...ng a linear loop inside another linear loop means this for loop is accidentally O(n2) — as the length of the string increases, the time this loop takes increases quadratically. Instead of doing that you could use the characters's string collection.
– ignaciohugog
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Advantages of stateless programming?
I've recently been learning about functional programming (specifically Haskell, but I've gone through tutorials on Lisp and Erlang as well). While I found the concepts very enlightening, I still don't see the practical side of the "no side effects" concept. What are the practical advantages of it? ...
How to join int[] to a character separated string in .NET?
...formance. Join method needs to know the size of the data to effectively preallocate necessary amount of memory.
Here is a part of internal implementation of String.Join method:
// length computed from length of items in input array and length of separator
string str = FastAllocateString(length);
f...
What are POD types in C++?
...pod<MyType>() to tell whether MyType is POD.
– allyourcode
Mar 31 '14 at 21:24
7
Bjarne Str...
Difference between dispatch_async and dispatch_sync on serial queue?
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I do mean serial execution. In point of view that all tasks are executed serial regards to other tasks in the same queue. Of cause it still can be concurrent regards to other queues. It is the whole point of GCD that tasks can be dispatched and executed concurrently.
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Unable to create a constant value of type Only primitive types or enumeration types are supported in
...I'm concerned about performance I should avoid doing this as it would load all data in memory first and then query it. Should I write raw sql for this scenarios?
– Arvand
Dec 28 '15 at 11:30
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Take the content of a list and append it to another list
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Take a look at itertools.chain for a fast way to treat many small lists as a single big list (or at least as a single big iterable) without copying the smaller lists:
>>> import itertools
>>> p = ['a', 'b', 'c']
>>> q = ['d', 'e', 'f']
>>> r = ['g', ...
Useful GCC flags for C
Beyond setting -Wall , and setting -std=XXX , what other really useful, but less known compiler flags are there for use in C?
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How to find out the number of CPUs using python
...sing Python. The result should be user/real as output by time(1) when called with an optimally scaling userspace-only program.
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Why does one hot encoding improve machine learning performance?
...e. The three possible values of w×x are 0, w and 2×w. Either these three all lead to the same decision (they're all < b or ≥b) or "UK" and "French" lead to the same decision, or "French" and "US" give the same decision. There's no possibility for the model to learn that "UK" and "US" should b...