What does '\0' mean?

Question

I can\'t understand what the \'\\0\' in the two different place mean in the following code:

string x = \"hhhdef\\n\";
cout << x << endl;
x[3]=\'\         


        

Answer 1

You're representing strings in two different ways here, which is why the behaviour differs.

The second one is easier to explain; it's a C-style raw char array. In a C-style string, '\0' denotes the null terminator; it's used to mark the end of the string. So any functions that process/display strings will stop as soon as they hit it (which is why your last string is truncated).

The first example is creating a fully-formed C++ std::string object. These don't assign any special meaning to '\0' (they don't have null terminators).