understanding pointers

Hi, I'm a new user at gamedev.net but I've known about the site for a long time .

so im new to c++ but not new to programming i have program for a while in c#.

so I've been watching the software engineering videos at 3d buzz and just wanted to make sure i understand pointers before i continue on.

here's my code with comments on what i comprehended :


]#include <iostream>

using namespace std;

int main()
{
int *ptr; // initialize a pointer ptr of type int
int x = 3; // initialize a variable X of type int to 3
ptr = &x // get the memory address of X by referencing it and assigning it to ptr

cout << "&ptr = " << &ptr << endl; // prints out the memory address of ptr
cout << "ptr = " << ptr << endl; // prints out ptr which has the memory address of X
cout << "&x = " << &x << endl; // prints out the memory address of X
cout << "x = " << x << endl; // prints the value of X
cout << "*ptr = " << *ptr << endl; // prints the dereference ptr which has the value of X
cout << endl;

int y = 23; // initialize a variable y of type int to 23
ptr = &y // get the memory address of Y by referencing it and assigning it to ptr
int **dptr = &ptr // declare a double pointer dptr and assign the memory address of ptr

cout << "&ptr = " << &ptr << endl; // prints out the memory address of ptr
cout << "ptr = " << ptr << endl; // prints out ptr which has the memory address of Y
cout << "&y = " << &y << endl; // prints out the memory address of Y
cout << "y = " << y << endl; // prints the value of Y
cout << "*ptr = " << *ptr << endl; // prints the dereference ptr which has the value of Y
cout << "dptr = " << dptr << endl; // prints out dptr which has the memory address of ptr
cout << "*dptr = " << *dptr << endl; // prints the dereference dptr which has the memory address of Y assigned to it

cout << "**dptr = " << **dptr << endl; // // prints the second(not sure of the word here) dereference of dptr which has the of Y

/* so basically what i gathered is when you have a & in front of a variable or pointer you get the memory address as the value.

when you have a pointer with a & and assign the reference of a variable the pointer now holds the memory address of said variable.

when we have a pointer without any * or & we get the memory address of the variable it was referencing.

when you dereference a pointer with * you are gaining the value of said variable that was referenced.

note:

i like to think of dereferencing as decrypting the memory address to gain access to the value of the variable (not sure if that analogy is correct).

when we have a double pointer (A) and assigning a reference to an other pointer(<img src='http://public.gamedev.net/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='B)' /> and just use the pointer(A) without any * or & we get the memory address of pointer(<img src='http://public.gamedev.net/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='B)' /> assigned into Pointer(A).

when we dereference it once we get the memory address of the variable that pointer(<img src='http://public.gamedev.net/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='B)' /> was pointing to and assign it into Pointer(A).

when we have a double dereference we get the value of the variable that pointer(<img src='http://public.gamedev.net/public/style_emoticons/<#EMO_DIR#>/cool.gif' class='bbc_emoticon' alt='B)' /> was pointing to and assign itinto Pointer(A). */

return 0;
}

so yes i know this may be a long read for some of you .

please let me know if I'm not correct or misunderstanding .

also i know that when reading it may sometimes that i have broken sentences as I'm not a good writer i tried to re-read everything to make sure its clear so if something is not clear let me know.

thank you for your time and help, its much appreciated.