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Pointer constants in C language

Definition  

As we store any data (information) in our memory, the computer also stores data in its memory. The computer memory is divided into a number of location called storage cells. Each location can hold one bye of data and each location is associated with address. Let us assume size of memory is 64K where 1K=1024bytes. So , total number of memory locations =64K = 64X 1K

= 64 X 1024 bytes

=65536 locations

Logically, all 65535 locations in computer memory are numbered sequentially from 0 to 65535 but, physically they are divided into even bank and odd bank. Even bank is set of memory locations with even address and odd bank is set of memory locations with odd addresses as shown as below:

Pointer constants in C


These memory addresses are called pointer constants. We cannot change them ; but, we can only use them to store data values.
for example, in the above memory organization, the address ranging from 0 to 65535 are pointer constants.

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Memory representation of Linked List Data Structures in C Language

Memory representation of Linked List

             In memory the linked list is stored in scattered cells (locations).The memory for each node is allocated dynamically means as and when required. So the Linked List can increase as per the user wish and the size is not fixed, it can vary.

               Suppose first node of linked list is allocated with an address 1008. Its graphical representation looks like the figure shown below:


      Suppose next node is allocated at an address 506, so the list becomes,



  Suppose next node is allocated with an address with an address 10,s the list become,


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