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C语言结构体里的成员数组和指针 - c++1y / stl - 清泛IT社区，为创新赋能！
...t;p的偏移之所以是0x8而不是0x6，是因为内存对齐了（我在64位系统上）。关于内存对齐，可参看《深入理解C语言》一文。好了，现在你知道为什么原题中会访问到了0x4的地址了吧，因为是相对地址。相对地址有很好多处，其可以...
MySQL error: key specification without a key length
...
64
You can specify the key length in the alter table request, something like:
alter table authors...
How do you specify that a class property is an integer?
... there is a bug in the VS plugin that is suggesting invalid types, perhaps based on the ECMA 262 list of reserved keywords (which includes "int")
– Josh
Oct 15 '12 at 21:09
...
Detecting endianness programmatically in a C++ program
...
I don't like the method based on type punning - it will often be warned against by compiler. That's exactly what unions are for !
bool is_big_endian(void)
{
union {
uint32_t i;
char c[4];
} bint = {0x01020304};
return b...
Fast stable sorting algorithm implementation in javascript
...lyfill to implement a stable sort regardless of the native implementation, based on the assertion made in this answer:
// ECMAScript 5 polyfill
Object.defineProperty(Array.prototype, 'stableSort', {
configurable: true,
writable: true,
value: function stableSort (compareFunction) {
...
How to get object size in memory? [duplicate]
...sure. It is an internal implementation detail and not documented. However, based on the objects included in the other object. Now, how do we calculate the memory requirement for our cached objects?
I had previously touched this subject in this article:
Now, how do we calculate the memory requir...
How to read a single char from the console in Java (as the user types it)?
...le input in Python and Java. Excerpt:
If your program must be console based,
you have to switch your terminal out
of line mode into character mode, and
remember to restore it before your
program quits. There is no portable
way to do this across operating
systems.
One of the sugges...
How do I replace NA values with zeros in an R dataframe?
...
The dplyr hybridized options are now around 30% faster than the Base R subset reassigns. On a 100M datapoint dataframe mutate_all(~replace(., is.na(.), 0)) runs a half a second faster than the base R d[is.na(d)] <- 0 option. What one wants to avoid specifically is using an ifelse() or ...
Javascript: Extend a Function
... javascript extension.
First let us extend javascript function.
function Base(props) {
const _props = props
this.getProps = () => _props
// We can make method private by not binding it to this object.
// Hence it is not exposed when we return this.
const privateMethod = ()...
Does pandas iterrows have performance issues?
...
Mateen Ulhaq
16.6k1111 gold badges6464 silver badges105105 bronze badges
answered Jul 21 '14 at 17:39
JeffJeff
1...