Pointer and Array

Pointer and Array

Meaning of Pointer

A variable that store the address of another variable

Two operators mostly used in pointer :

• ·         * (Content of)

So the (*) symbol in (*ptr) for example is used to point the content in ptr variable

• ·         & (Address of)

The (&) symbol in (ptr = &x) is used to show where the x  address is

Pointer to Pointer (**)

A variable that saves another address of a pointer

So when the second pointer get the address of the first pointer using the (&) symbol, it ( the second pointer ) can point the content of that address using the (**) symbol.

Meaning of Array

A series of elements of the same type placed in contiguous memory locations that can be individually referenced by adding an index to a unique identifier

•       Syntax:

                                type array_value [value_dim];

•       Example :

                                int A[10];

           Elements of an array indexed starting from 0

Two Dimensional Array

•       Syntax 2D Array:

                                type name_array[row][col];

•       Example:

                                int a[2][0];

String

An array of character that ended with a null character ( ‘\0’ )

•       Example :

                char s [  ] =  ”Makan”;                      

                Similar to :

                char s[ ] = {’M’,’a’,’k’,’a’,’n’,’\0’};

The fuction to manipulate string is ( #include<string.h> )