A fine question, but a little too broad (IMO). That's called the scope-resolution operator, and your search term for further learning is scope. All those names (cout, member functions of A) are …

I am a C guy and I'm trying to understand some C++ code. I have the following function declaration:

95 .cpp is the recommended extension for C++ as far as I know. Some people even recommend using .hpp for C++ headers, just to differentiate from C. Although the compiler doesn't care …

Mar 17, 2011 · What does this symbol mean? AirlineTicket::AirlineTicket ()@PaulR Not everyone who arrives upon this question is looking to learn C++. I, for example, just happened to be …

Nov 24, 2017 · This is called the three-way comparison operator. According to the P0515 paper proposal: There’s a new three-way comparison operator, <=>. The expression a <=> b returns …

This question is not an exact duplicate of the What should main () return in C and C++?. However, everything that it asks is already answered over there in greater detail and in greater quality, …

To those who are looking for speed: count and find are nearly identical in speed when using maps that require unique keys. (1) If you don't need the elements to maintain a specific order, use …

itoa will be faster than the stream equivalent. There are also ways of re-using the string buffer with the itoa method (avoiding heap allocations if you are frequently generating strings. e.g. for …

In my project code, I found that someone used #ifdef and #if in code. I would like to know what does purpose for using them? As my knowledge, it said to the preprocessor will not do …

33 Cpp Reference is always helpful!!! Details about explicit specifier can be found here. You may need to look at implicit conversions and copy-initialization too. Quick look The explicit specifier …