4.1 Pointers

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Pointers: -

  • A pointer is a special variable that stores the memory address of another variable.
  • Instead of holding a direct value (like 10 or 3.5), a pointer holds the location where the value is stored in memory.
  • Pointers are powerful in C programming because they allow direct access to memory, dynamic memory allocation, and efficient data manipulation.
  • Every variable in C is stored at a specific memory location, identified by a unique address.
  • The address-of operator (&) is used to get the address of a variable.
  • %p format specifier is used to print an address in pointer format.

 

Declaring Pointer Variables: -

  • A pointer variable is declared using an asterisk (*) before the variable name.
  • The data type of the pointer must match the data type of the variable it points to.



Initialization of Pointer Variables: -

  • A pointer should always be initialized before using it.
  • We can initialize a pointer by assigning it the address of a variable using the address-of operator (&).
  • If a pointer is not initialized, it may contain a garbage address, which can cause runtime errors if dereferenced.



Accessing a Variable through its Pointer: -

The dereference operator (*) is used to access (read or modify) the value of the variable a pointer points to. This process is called dereferencing.





            Example: -


            Output: -



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