大约有 42,000 项符合查询结果（耗时：0.0360秒） [XML]
How much is the overhead of smart pointers compared to normal pointers in C++?
...ude <thread>
uint32_t n = 100000000;
void t_m(void){
auto a = (char*) malloc(n*sizeof(char));
for(uint32_t i=0; i<n; i++) a[i] = 'A';
}
void t_u(void){
auto a = std::unique_ptr<char[]>(new char[n]);
for(uint32_t i=0; i<n; i++) a[i] = 'A';
}
void t_u2(void){
a...
Why declare a struct that only contains an array in C?
...ever you declare such an object. This could also be achieved with
typedef char ABC[MAX];
but then you have a much bigger problem: you have to be aware that ABC is an array type (even though you can't see this when you declare variables of type ABC) or else you'll get stung by the fact that ABC wi...
C++ convert hex string to signed integer
...iostream>
using namespace std;
int main() {
string s = "abcd";
char * p;
long n = strtol( s.c_str(), & p, 16 );
if ( * p != 0 ) { //my bad edit was here
cout << "not a number" << endl;
}
else {
cout << n << endl;
}
}
...
Remove not alphanumeric characters from string
...
Removing non-alphanumeric chars
The following is the/a correct regex to strip non-alphanumeric chars from an input string:
input.replace(/\W/g, '')
Note that \W is the equivalent of [^0-9a-zA-Z_] - it includes the underscore character. To also rem...
Can I escape html special chars in javascript?
...lay a text to HTML by a javascript function. How can I escape html special chars in JS? Is there an API ?
15 Answers
...
SQL - The conversion of a varchar data type to a datetime data type resulted in an out-of-range valu
...table). In comment you said you want it in yyyy-mm-dd format. So, try this SELECT CONVERT(char(10), GetDate(),126). Just replace GETDATE() with necessary value.
– Mahe
Dec 30 '13 at 15:29
...
Secure random token in Node.js
..."Base 64 Encoding with URL and Filename Safe Alphabet". IMO, replacing the characters is "elegant enough".
– natevw
Oct 7 '13 at 21:58
8
...
Standard alternative to GCC's ##__VA_ARGS__ trick?
...ine REST_HELPER_TWOORMORE(first, ...) , __VA_ARGS__
#define NUM(...) \
SELECT_10TH(__VA_ARGS__, TWOORMORE, TWOORMORE, TWOORMORE, TWOORMORE,\
TWOORMORE, TWOORMORE, TWOORMORE, TWOORMORE, ONE, throwaway)
#define SELECT_10TH(a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, ...) a10
int
main...
How to match “any character” in regular expression?
...
Yes, you can. That should work.
. = any char
\. = the actual dot character
.? = .{0,1} = match any char zero or one times
.* = .{0,} = match any char zero or more times
.+ = .{1,} = match any char one or more times
...
How to generate a core dump in Linux on a segmentation fault?
...oid);
static void cleanup(void);
void init_signals(void);
void panic(const char *, ...);
struct sigaction sigact;
char *progname;
int main(int argc, char **argv) {
char *s;
progname = *(argv);
atexit(cleanup);
init_signals();
printf("About to seg fault by assigning zero to *s\n...