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Why malloc+memset is slower than calloc?
...take small allocations (anything from 1 byte to 100s of KB) and group them into larger pools of memory. For example, if you allocate 16 bytes, malloc() will first try to get 16 bytes out of one of its pools, and then ask for more memory from the kernel when the pool runs dry. However, since the pr...
Why isn't vector a STL container?
... &x = b[5]; // that's what really happens
bool y = b[5]; // implicitly converted to bool
assert(b[5] == false); // converted to bool
assert(b[6] == b[7]); // bool operator==(const reference &, const reference &);
b[5] = true; // assignment on reference
assert(b[5] == true); // and actua...
Static function variables in Swift
...t. Try declaring a private struct with static variable.
func foo() -> Int {
struct Holder {
static var timesCalled = 0
}
Holder.timesCalled += 1
return Holder.timesCalled
}
7> foo()
$R0: Int = 1
8> foo()
$R1: Int = 2
9> foo()
$R2: Int = 3
...
Django Rest Framework File Upload
... very helpful thank you a lot. But i don't understand, why you are converting dict data to QueryDict in parser? In my case in Django, normal dictionary data work perfectly without converting.
– Metehan Gülaç
Apr 12 at 20:15
...
How to get an enum which is created in attrs.xml in code
...6 in your example
if (a.hasValue(R.styleable.IconView_icon)) {
int value = a.getInt(R.styleable.IconView_icon, 0));
}
a.recycle();
}
If you want the value into an enum you would need to either map the value into a Java enum yourself, e.g.:
private enum Format {
enum_name_...
Why does sizeof(x++) not increment x?
...ype. The size is determined from the type of the operand. The result is an integer. If the type of the operand is a variable length array type, the operand is evaluated; otherwise, the operand is not evaluated and the result is an integer constant.
...
What are the options for storing hierarchical data in a relational database? [closed]
... thought I'd give Celko a bit of competition by coming up with a method to convert an Adjacency List to Nested sets at speeds that just seem impossible. Here's the performance of the push stack method on my i5 laptop.
Duration for 1,000 Nodes = 00:00:00:870
Duration for 10,000 Nodes = 00:01...
What are the differences between the BLOB and TEXT datatypes in MySQL?
...
TEXT and CHAR will convert to/from the character set they have associated with time. BLOB and BINARY simply store bytes.
BLOB is used for storing binary data while Text is used to store large string.
BLOB values are treated as binary strings ...
Check whether number is even or odd
...
You can use the modulus operator, but that can be slow. If it's an integer, you can do:
if ( (x & 1) == 0 ) { even... } else { odd... }
This is because the low bit will always be set on an odd number.
share
...
SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
...have CourseID on table Category?
Maybe you should restructure your schema into this,
CREATE TABLE Categories
(
Code CHAR(4) NOT NULL PRIMARY KEY,
CategoryName VARCHAR(63) NOT NULL UNIQUE
);
CREATE TABLE Courses
(
CourseID INT NOT NULL PRIMARY KEY,
BookID INT NOT NULL,
CatCode CHAR(4) ...