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Why can't variables be declared in a switch statement?
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Case statements are only labels. This means the compiler will interpret this as a jump directly to the label. In C++, the problem here is one of scope. Your curly brackets define the scope as everything inside the switch statement. This means that you are left with a scope where a jump ...
Why can I not push_back a unique_ptr into a vector?
... guarantees that a single unique_ptr container has ownership of the held pointer. This means that you can't make copies of a unique_ptr (because then two unique_ptrs would have ownership), so you can only move it.
Note, however, that your current use of unique_ptr is incorrect. You cannot use it ...
Difference between encoding and encryption
... want to store text on a hard drive, you're going to have to find a way to convert your characters to bits. Alternatively, if all you have is a flash light, you might want to encode your text using Morse. The result is always "readable", provided you know how it's stored.
Encryption means you want ...
Possible to iterate backwards through a foreach?
...also an essential part of modern iterator-based programming. Perhaps the point is that it would be clearer/safer if there were two distinct keywords, to clarify whether one is asserting that the iterations are order-independent? [Given a language like Eiffel that can propagate contracts, such assert...
Differences in boolean operators: & vs && and | vs ||
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Those are the bitwise AND and bitwise OR operators.
int a = 6; // 110
int b = 4; // 100
// Bitwise AND
int c = a & b;
// 110
// & 100
// -----
// 100
// Bitwise OR
int d = a | b;
// 110
// | 100
// -----
// 110
System.out.println(c); // 4
System.out.pr...
Select all elements with “data-” attribute without using jQuery
...`[data-foo="${i}"]`)
Note even if you don't write value in string it gets converted to string like if I write
<div data-foo=1></div>
and then inspect the element in Chrome developer tool the element will be shown as below
<div data-foo="1"></div>
You can also cross verify ...
How do I get the height and width of the Android Navigation Bar programmatically?
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Try below code:
Resources resources = context.getResources();
int resourceId = resources.getIdentifier("navigation_bar_height", "dimen", "android");
if (resourceId > 0) {
return resources.getDimensionPixelSize(resourceId);
}
return 0;
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How to check if all list items have the same value and return it, or return an “otherValue” if they
...ts, see this question. In that cases, you need to implement the IEquatable interface.
– Matt
May 14 '14 at 14:46
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Static variables in member functions
...A::foo() is a non-template function. There will be only one copy of static int i inside the program.
Any instance of A object will affect the same i and lifetime of i will remain through out the program. To add an example:
A o1, o2, o3;
o1.foo(); // i = 1
o2.foo(); // i = 2
o3.foo(); // i = 3
o1.f...
What is the most efficient Java Collections library? [closed]
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I've worked on quite a few data intensive projects where collections were a huge bottleneck. Java Collections are terribly inefficient (both memory and speed) especially if they store primitives.
– Jay Askren
Sep 25 '...