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Checking to see if one array's elements are in another array in PHP
I have two arrays in PHP as follows:
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Does MongoDB's $in clause guarantee order
When using MongoDB's $in clause, does the order of the returned documents always correspond to the order of the array argument?
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In laymans terms, what does 'static' mean in Java? [duplicate]
I have been told several definitions for it, looked on Wikipedia, but as a beginner to Java I'm still not sure what it means. Anybody fluent in Java and idiot?
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Length of generator output [duplicate]
Python provides a nice method for getting length of an eager iterable, len(x) that is. But I couldn't find anything similar for lazy iterables represented by generator comprehensions and functions. Of course, it is not hard to write something like:
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Why use #ifndef CLASS_H and #define CLASS_H in .h file but not in .cpp?
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First, to address your first inquiry:
When you see this in .h file:
#ifndef FILE_H
#define FILE_H
/* ... Declarations etc here ... */
#endif
This is a preprocessor technique of preventing a header file from being included multiple times, which can ...
Fragment transaction animation: slide in and slide out
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UPDATE For Android v19+ see this link via @Sandra
You can create your own animations. Place animation XML files in res > anim
enter_from_left.xml
<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/andr...
What is the difference between bottom-up and top-down?
The bottom-up approach (to dynamic programming) consists in first looking at the "smaller" subproblems, and then solve the larger subproblems using the solution to the smaller problems.
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What are the differences between virtual memory and physical memory?
I am often confused with the concept of virtualization in operating systems. Considering RAM as the physical memory, why do we need the virtual memory for executing a process?
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Find all files in a directory with extension .txt in Python
How can I find all the files in a directory having the extension .txt in python?
26 Answers
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Why is there a difference in checking null against a value in VB.NET and C#?
In VB.NET this happens:
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