Pointers with other operators

Pointer with different operators :

Pointer with Assignment operator :

We know that we can assign value of a simple variable into another variable by using assignment operator ( = ) for e.g.

 int a = 90 , b = 80  ;

By performing the activity given above you would find that all arrays declared in C++ are nothing but a const pointer having the addressof the first element of the same array. 

  b = a ; //The value of b is being replaced by the value of a  i.e. 90 

Similarly we can use assignment operator ( = ) between two pointer variables. So the following code snippet is very correct:

      int x = 45 , y = 78 ;
      int * a   = &x , *b = &y;
      a = b ; // assigning pointers to each other

When we write pointer a = b then the address which is being stored in b i,e a Hexadecimal value , gets copied into pointer a removing any of its previous contents (address).

Pointer with comparison operator (==)

Just like we use comparison operator (==) between two simple variables, we can also use it between two pointer variables.
What would be the output of the following code :

 main ( )
 {
   int a = 30 , b = 30 ;
   if ( a == b)
     cout<< “I Liked this study material”;
   else
     cout<< “Who has made it yaar!!”;
 }

Yes, you are absolutely right the output would be "I Liked this study material”, because the conditional expression a == b is evaluated to be true.
Now try to predict the output of the following code:

 main( )
 {
  int a = 30 , b = 30 ;
  int *p = &a ;
  int *q = &b ;
  if ( p == q)
    cout << “Kamal, Are you joking !”;
  else
    cout<< “Pointer is so easy following this study material”;
 }

If you are not able to find the answer yourself, execute the code and discuss with your teacher.

Note : Similarly we can also use != between two pointer variables.Sometimes we also compare a pointer variable with NULL or ‘\0’ to check whether it is pointing No where.