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#pragma pack effect
...essing variables that are not aligned properly. For example, given 4-byte integers and the following struct:
struct Test
{
char AA;
int BB;
char CC;
};
The compiler could choose to lay the struct out in memory like this:
| 1 | 2 | 3 | 4 |
| AA(1) | pad..................
Forward declaration of nested types/classes in C++
...
class IDontControl
{
class Nested
{
Nested(int i);
};
};
I needed a forward reference like:
class IDontControl::Nested; // But this doesn't work.
My workaround was:
class IDontControl_Nested; // Forward reference to distinct name.
Later when I could use th...
How do I get the title of the current active window using c#?
...nd-caption-with-windows-api-in-c/
[DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();
[DllImport("user32.dll")]
static extern int GetWindowText(IntPtr hWnd, StringBuilder text, int count);
private string GetActiveWindowTitle()
{
const int nChars = 256;
StringBuilder Buff...
How to break out or exit a method in Java?
...em.exit(0);
Java language provides three jump statemnts that allow you to interrupt the normal flow of program.
These include break , continue ,return ,labelled break statement
for e.g
import java.util.Scanner;
class demo
{
public static void main(String args[])
{
outerLo...
How to handle back button in activity
... // your code.
}
older than API 5
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
// your code
return true;
}
return super.onKeyDown(keyCode, event);
}
...
Is there a standard sign function (signum, sgn) in C/C++?
...one has posted the type-safe C++ version yet:
template <typename T> int sgn(T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations...
How can I multiply and divide using only bit shifting and adding?
...ion)
(_2 means base 2)
As you can see, multiplication can be decomposed into adding and shifting and back again. This is also why multiplication takes longer than bit shifts or adding - it's O(n^2) rather than O(n) in the number of bits. Real computer systems (as opposed to theoretical computer s...
Download a single folder or directory from a GitHub repo
...ia SVN. If you checkout your code with subversion, Github will essentially convert the repo from git to subversion on the backend, then serve up the requested directory.
Here's how you can use this feature to download a specific folder. I'll use the popular javascript library lodash as an example.
...
What is the best way to use a HashMap in C++?
...by the key, insert and access is in O(log n). Usually the standard library internally uses red black trees for ordered maps. But this is just an implementation detail. In an unordered map insert and access is in O(1). It is just another name for a hashtable.
An example with (ordered) std::map:
#in...
MySQL JOIN the most recent row only?
... a synonym for INNER JOIN.
Test case:
CREATE TABLE customer (customer_id int);
CREATE TABLE customer_data (
id int,
customer_id int,
title varchar(10),
forename varchar(10),
surname varchar(10)
);
INSERT INTO customer VALUES (1);
INSERT INTO customer VALUES (2);
INSERT INTO custo...