If you read the website you will realize that this is a simple C++ wrapper over a C library. A typical issue with C library are buffer overruns: Try this program: Because the buffer can only contain 16 characters, the remaining characters will be written past its end. This is stack smashing, and undefined behavior. A number … Read more
Modern C++ makes this super simple. C++20 C++20 introduces std::format, which allows you to do exactly that. It uses replacement fields similar to those in python: Code from cppreference.com, CC BY-SA and GFDL Check out the compiler support page to see if it’s available in your standard library implementation. As of 2021-11-28, full support is only available in Visual Studio 2019 16.10, which … Read more
In general, returning a reference is perfectly normal and happens all the time. If you mean: That is all sorts of evil. The stack-allocated i will go away and you are referring to nothing. This is also evil: Because now the client has to eventually do the strange: Note that rvalue references are still just references, so … Read more
A: The std::string class has a constructor that takes a char const*, so you simply create an instance to do your conversion. B: Instances of std::string have a c_str() member function that returns a char const* that you can use to convert back to char const*.
C++ std::strings are “counted” strings – i.e., their length is stored as an integer, and they can contain any character. When you replace the third character with a \0 nothing special happens – it’s printed as if it was any other character (in particular, your console simply ignores it). In the last line, instead, you are printing a … Read more
Just follow closely the chain of events. Grab 10 Grab 20 Grab 30 Grab EOF Look at the second-to-last iteration. You grabbed 30, then carried on to check for EOF. You haven’t reached EOF because the EOF mark hasn’t been read yet (“binarically” speaking, its conceptual location is just after the 30 line). Therefore you … Read more
Input one number at a time, and check whether the following character is ,. If so, discard it.
size_type is a (static) member type of the type vector<int>. Usually, it is a typedef for std::size_t, which itself is usually a typedef for unsigned int or unsigned long long.
It’s to access a member function or member variable of an object through a pointer, as opposed to a regular variable or reference. For example: with a regular variable or reference, you use the . operator to access member functions or member variables. But if you’re working with a pointer, you need to use the -> operator: It can also … Read more
Note: Most of the answers cover function pointers which is one possibility to achieve “callback” logic in C++, but as of today not the most favourable one I think. What are callbacks(?) and why to use them(!) A callback is a callable (see further down) accepted by a class or function, used to customize the current logic … Read more