What is different between "&" and "*" to declare a pointer?

Answer 1

& is the address-of operator.
* is the point-to operator.

int *r = 0;
int s = 0;

// declaring a pointer and a variable.

r = &s;

// assign address of s to r.

cout << *r;

// tells program to print whatever the address stored in r points to.

Answer 2

In

int &p;

The "&" here isn't used as a operator. It denotes a reference instead of a pointer to an object.

I suggest you to take a look at the differences between a pointer and a reference.

https://www.quora.com/What-are-the-differences-between-references-and-pointers

Answer 3

what is:
int &p;

Answer 4

tnx