Now I am a freshman, and I hope to become a qualified programmer in the future. I just learned C++. I would like to start this blog to record my growth path. At the same time, I also hope that my blog will play the role of a memo, recording some small details encountered in the process of writing code.
Quote:
A reference to a variable is equivalent to the variable, which is equivalent to the variable's alias.
int n=1;
int &a=n;//a is a reference to n, and a is of type int &
Only variables can be referenced, constants and expressions cannot be referenced
int n=1;
int &a=n*2;//Compile error
int &a=1;//Compile error
A reference can also be used as the return value of a function
int &p() {return n;}
This allows the function to be placed on the left side of the assignment operator, as in p()=1;
When defining a reference, add the const keyword in front of it, which is a constant reference
int n=1;
const int &a=n;
The key point is that you cannot modify the content of its reference through frequent references
Such as:
int n=1;
const int &a=n;
a++;//Compile error
n++;//n=2
A const reference can be initialized by a general reference, and a general reference cannot be initialized by a const reference
Such as:
int &a=const &n;//Compile error
const &a=int &n;//compiles correctly