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Why unsigned integer is not available in PostgreSQL?
I came across this post ( What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL? ) and realized that PostgreSQL does not support unsigned integer.
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Undefined, unspecified and implementation-defined behavior
...n the program!
Let's look at a classic example:
#include <iostream>
int main()
{
char* p = "hello!\n"; // yes I know, deprecated conversion
p[0] = 'y';
p[5] = 'w';
std::cout << p;
}
The variable p points to the string literal "hello!\n", and the two assignments below ...
How do I get the first element from an IEnumerable in .net?
...e enumerable contains more than one item.
Edit: Thanks Marc Gravell for pointing out that I need to dispose of my IEnumerator object after using it - I've edited the non-LINQ example to display the using keyword to implement this pattern.
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How to simplify a null-safe compareTo() implementation?
... .thenComparing(Metadata::getValue, nullSafeStringComparator);
public int compareTo(Metadata that) {
return metadataComparator.compare(this, that);
}
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appending array to FormData and send via AJAX
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You have several options:
Convert it to a JSON string, then parse it in PHP (recommended)
JS
var json_arr = JSON.stringify(arr);
PHP
$arr = json_decode($_POST['arr']);
Or use @Curios's method
Sending an array via FormData.
Not recommended: Seriali...
Difference between null and empty (“”) Java String
...not, 20 is a number). Same case for null: it's not a string, but it can be converted to one if you try to add it.
– daboross
Mar 4 '18 at 9:13
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Using scanf() in C++ programs is faster than using cin?
...and XOR all of the numbers.
iostream version:
#include <iostream>
int main(int argc, char **argv) {
int parity = 0;
int x;
while (std::cin >> x)
parity ^= x;
std::cout << parity << std::endl;
return 0;
}
scanf version:
#include <stdio.h>
int main...
Declaring a custom android UI element using XML
...get this
a.recycle();
}
R.styleable.MyCustomView is an autogenerated int[] resource where each element is the ID of an attribute. Attributes are generated for each property in the XML by appending the attribute name to the element name. For example, R.styleable.MyCustomView_android_text contai...
What does the comma operator , do?
... comma operation will always be the value of the last expression. At no point will i have the values 5, 4, 3, 2 or 1. It is simply 0. It's practically useless unless the expressions have side effects.
– Jeff Mercado
Nov 13 '10 at 7:06
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What does value & 0xff do in Java?
...is is necessary is that byte is a signed type in Java. If you just wrote:
int result = value;
then result would end up with the value ff ff ff fe instead of 00 00 00 fe. A further subtlety is that the & is defined to operate only on int values1, so what happens is:
value is promoted to an i...