Answer 1

Both serve same purpose.
Using reference will make alias name. Using pointer will make a new pointer variable which can be reassigned..

Edit:
Hope this helps, for more details.
https://hackr.io/blog/pass-by-reference-vs-pass-by-pointer

Answer 2

That was not address-of operator, that was the aymbol to signify that <a> and <b> are `int` references.

Read here for difference between pointers and references.

https://techdifferences.com/difference-between-pointer-and-reference-2.html

In regards to parameters, no operator is expected, cause arguments are to be used (and occasionally modified), but not to be evaluated (one of the purpose of operators - to evaluate and return).

Answer 3

Hope this example helps...

#include <iostream>
using namespace std;
void sum(int &a, int &b){
a = 12, b =15;
}

int main() {
int a = 3, b = 5;

cout << a << b <<endl;
sum(a,b);
cout << a << b;
return 0;
}

Actual parameter value gets stores in formal parameter address so that formal parameter changes reflect back on actual parameters..
It's like pass by reference.

Answer 4

Yes. It now deal with pointers..

#include <iostream>
using namespace std;
void sum(int *a, int *b){
*a = 12, *b =15;
}

int main() {
int a = 3, b = 5;

cout << a << b <<endl;
sum(&a,&b);
cout << a << b;
return 0;
}

Answer 5

Manav Roy
When we see & symbol in parameters list, it defines that the parameter is expected as a reference.

When we see & symbol inside the function body, global space (anywhere but the parameters list), then it could either be address-of operator (unary - with one operand), or binary AND operator (binary - with two operands on its left and right side).

Pointers came with C, references came with C++. C recognizes pointers but not references. C++ recognises both pointers and references.

More about the differences between pointers and references, you may find in the link in my earlier post.

Answer 6

Skksk