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POINTERS---

Dynamic memory allocation cannot be performed without using pointers, so it is necessary to learn a pointers.
A pointer is a variable which holds the address of the another variable.
Pointer is also declared as other variable declared, but it use a asterisk(*) symbol, to represent that it is a pointer.

 Syntax:- data_types *variable_name;

 Example:-  int *p; // integer pointer

 Note:- A pointer can hold the address of that variable, which is same as pointer data types,i.e data types of pointer variable=data types of other variable.
          Every variable is a memory location, and every memory location has its own address which can be accessed by using ampersand(&) operator.

 Program:- to print the address of a variable: 
Use Pointer:- 


  • define a pointer variable
  • assign the address of the other variable into pointer variable
  • access the value at the address, from the pointer variable.It is done by using unary(*) operator. 
Program 2:- using a pointer variable
NOTE:- A pointer assigned NULL is known as null pointer,that is this pointer variable having value 0

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