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cpp-pointers
============

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   | **Source:**
     https://foxhop.net/f3aadc3e-2f95-11f1-98f8-e86a64d24d78/cpp-pointers
   | **Snapshot:** 2026-10-16T08:17:01Z
   | **Generator:** Remarkbox ``d747782``

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cpp Pointers
============

**if p is a pointer**

&p
   the memory address of p

\*p
   the content that p points to

p
   the content of p (or the address that p points to)

Dynamic memory allocation or alias
----------------------------------

**Useful but dangerous...**

.. container::
   :name: cb1

   ::

      int *p, *q; // create two pointers, named p and q

      p = new int; // 

      *p = 100;

      q = p;

      *q = 200;

      q = new int;

      *q = *p;

      delete p; // give memory that p occupied back to operating system

      p = NULL; // set p to memory address 0  

      delete q; // give memory that q occupied back to operating system

      q = NULL; // set q to memory address 0

Dynamic Allocation for arrays
-----------------------------

.. container::
   :name: cb2

   ::

      int size = 5;         // create an integer
      int *A;               // create an array of pointers

      A = new int[ size ];  // Ask for a certain size for your array

      A[0] = 10;            // Give values to Array
      A[1] = 20;
      A[2] = 30;
      A[3] = 40; 
      A[4] = 50; 

      //       8    32   32       36       40
      cout << &A << A << A + 0 << A + 1 << A + 2

      //       10      28      30
      cout << A[0] << A[1] << A[2] 

      //       10      10       28        30
      cout << *A << *A + 0 << A + 1 << * A + 2

      delete []A;
      A = NULL;

--------------

| **Source:**
  https://foxhop.net/f3aadc3e-2f95-11f1-98f8-e86a64d24d78/cpp-pointers
| **Snapshot:** 2026-10-16T08:17:01Z
| **Generator:** Remarkbox ``d747782``