Answer to Question #220202 in C++ for suk

Question

You are given this snippet:

int main(){
    int m = 10, n = 20;
    cout << &m << endl;     // Whats is &m?
    int* ptr1 = &m;         // Explain this line.
    cout << ptr1 << endl;   // What is ptr1?
    cout << *ptr1 << endl;  // What is *ptr?
    int* ptr2 = ptr1;       // Explain this line.
    ptr1 = &n;              // Explain this line.
    cout << &ptr1 << endl;  // What is &ptr?
    return 0;
}

Please answer the questions in comments,

Answer 1

What is &m? &m gives the memory address to the integer variable m.

int* ptr1 = &m; ptr1 stores the address of variable m.

ptr1 prints content of ptr (address of m).

* ptr1 dereference ptr by *ptr (= m)

int* ptr2 = ptr1;ptr2 points to the same address (of m)

ptr1 = &n; ptr1 now points to n

&ptr1 output 19.