17 Oktober 2018 - Pointer and Arrays

Pointer and Array

Pointer and array:

• Pointer Definition 
• Array Definition
• Array Initialization 
• Array

A. Pointer Definition

     Pointer is a variable that store the address of another variable

     Syntax :

   <type> *ptr_name;

     Two operators mostly used in pointer : * (content of) and & (address of)

     Example: 

     Initialize an integer pointer into a data variable: 

     int i, *ptr;

     ptr = &i;

     To assign a new value to the variable pointed by the pointer:

     *ptr = 5;  /* means i=5 */ 

B. Array Definition

     Data saved in a certain structure to be accessed as a group or individually. Some variables saved         using the same name distinguish by their index.

     Array characteristics:

•      Homogenous
•      All elements have similar data type
•      Random Access
•      Each element can be reached individually, does not have to be sequential

     Syntax:

type array_value [value_dim];

     Example :

int A[10];

     The definition consists of 4 components:

• Type specified
• Identifier (name of the array)
• Operator index ([  ])
• Dimensional value inside operator [ ]

C. Array Initialization

     Array can be initialized explicitly without dimensional value declaration

     Example: 

int B[ ]={1, 2, -4, 8};