How can I change the variable to which a C++ reference refers?

Question

If I have this:

int a = 2;
int b = 4;
int &ref = a;

How can I make ref refer to b after this code?

Answer 1

You can't reassign a reference, but if you're looking for something that would provide similar abilities to this you can do a pointer instead.

int a = 2;
int b = 4;
int* ptr = &a;  //ptr points to memory location of a.
ptr = &b;       //ptr points to memory location of b now.

You can get or set the value within pointer with: 

*ptr = 5;     //set
int c = *ptr; //get