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What is the best way to use a HashMap in C++?
...gt;
#include <iostream>
#include <cassert>
int main(int argc, char **argv)
{
std::map<std::string, int> m;
m["hello"] = 23;
// check if key is present
if (m.find("world") != m.end())
std::cout << "map contains key world!\n";
// retrieve
std::cout << m["...
What is the most efficient/elegant way to parse a flat table into a tree?
...r_id = 1
ORDER BY f.name;
Re comment from @Nate:
SELECT f.name, GROUP_CONCAT(b.ancestor_id order by b.path_length desc) AS breadcrumbs
FROM FlatTable f
JOIN ClosureTable a ON (f.id = a.descendant_id)
JOIN ClosureTable b ON (b.descendant_id = a.descendant_id)
WHERE a.ancestor_id = 1
GROUP BY...
How to Copy Text to Clip Board in Android?
... }
return "";
}
@SuppressLint("NewApi")
public CharSequence coerceToText(Context context, ClipData.Item item) {
// If this Item has an explicit textual value, simply return that.
CharSequence text = item.getText();
if (text != null) {
r...
“register” keyword in C?
...at the variable does not alias with
anything else in the program (not even char's).
That can be exploited by modern compilers in a variety of situations, and can help the compiler quite a bit in complex code - in simple code the compilers can figure this out on their own.
Otherwise, it serves no p...
How can I use UUIDs in SQLAlchemy?
...min, you can't edit records because it implicitly tries to do some sort of character conversion for the "select * from table where id =..." and there's miscellaneous display issues.
Other than that everything seems to work fine, and so I'm throwing it out there. Leave a comment if you see a glaring...
Add … if string is too long PHP [duplicate]
...lay the whole field, but on the other, I just want to display the first 50 characters. If the string in the description field is less than 50 characters, then it won't show ... , but if it isn't, I will show ... after the first 50 characters.
...
Fastest way to reset every value of std::vector to 0
...ATIONS = 100000;
const size_t TEST_ARRAY_SIZE = 10000;
int main(int argc, char** argv) {
std::vector<int> v(TEST_ARRAY_SIZE, 0);
for(size_t i = 0; i < TEST_ITERATIONS; ++i) {
#if TEST_METHOD == 1
memset(&v[0], 0, v.size() * sizeof v[0]);
#elif TEST_METHOD == 2
...
What are copy elision and return value optimization?
...;iostream>
using namespace std;
class ABC
{
public:
const char *a;
ABC()
{ cout<<"Constructor"<<endl; }
ABC(const char *ptr)
{ cout<<"Constructor"<<endl; }
ABC(ABC &obj)
{ cout<<"copy constructor"<<endl;...
Throw keyword in function's signature
...lowing code?
#include <iostream>
void throw_exception() throw(const char *)
{
throw 10;
}
void my_unexpected(){
std::cout << "well - this was unexpected" << std::endl;
}
int main(int argc, char **argv){
std::set_unexpected(my_unexpected);
try{
throw_excepti...
How do I handle newlines in JSON?
...tf.org/rfc/rfc4627.txt contains this sentence in section 2.5: "All Unicode characters may be placed within the quotation marks except for the characters that must be escaped: quotation mark, reverse solidus, and the control characters (U+0000 through U+001F)." Since a newline is a control character,...