Two weeks ago, I came across an interesting bug. The convert() function
below returns 0x80000001 when p points to 0x01,
0x00, 0x00, 0x80, but the expected return value is
0x00000001 instead.
int32_t convert(const uint8_t *restrict p) {
uint32_t x = ( p[0] +
256 * p[1] +
256 * 256 * p …C++11 introduced three new smart pointer class templates:
std::unique_ptr, std::shared_ptr, and std::weak_ptr.
These smart pointer class templates are designed to replace the old
std::auto_ptr smart pointer, which is known to have some defect and
deprecated now. In this post, I would …
Today I have encountered a problem: Given that there are multiple equivalent
keys in an instance of std::multimap, how could we list all of the
corresponding values? For example:
#include <map>
#include <iostream>
int main() {
std::multimap<int, int> xs;
xs.insert(std::make_pair(1, 12));
xs.insert …It is a well-known idiom to define a virtual destructor for the classes with virtual functions. If we don't define a virtual destructor, then the base class destructor will be invoked when you are deleting the object through the base class pointer even if the object is an instance of …
I used to feel that the private inheritence is useless. Although we can
implement the has-a semantics with private inheritence, it provides little
benefits compared with object composition. Besides, in order to expose the
privately inherited members to public, C++ introduced an awkward syntax, i.e.
the using directives. These …
To sort the doubly linked list std::list, we can simply call the
sort() member function. For example,
#include <iostream>
#include <list>
int main() {
std::list<int> xs{5, 4, 3, 2, 1};
xs.sort(); // Sort the std::list!
for (auto &x : xs) {
std::cout << x << std::endl;
}
}
We can't …
I used to believe that iterators will be invalidated after calling the
member functions insert() or erase() of containers. Thus, I
would adopt a conservative approach:
For example, to remove …
