“Essential Concepts of Data Structures and Signal Systems: Understanding Key Structures in Programming and the Difference Between Analog and Digital Technologies”

Summarize the concepts of Data structures

1. INTRODUCTION A Data Structure is a storage that is used to store and organize data. It is way of arranging data on a computer so that it can be accessed and u pdate efficiently.  It is used for processing, retrieving, and storing data. Data Structures have a wide&diverse scope of usage across the fields of Computer Science and Software Engineering. To store a set of fixed key words which are referenced very frequently, and to store the customer order information in a drive in burger place.   For eg: Customers keep on coming & they have to get their correct food at the payment / food collection window. To store the genealogy information of Biological species.

2. Classification of Data Structures:                        There are many different data structures that are used to solve different mathematical & logical problems. By using data structures, one can organize & process a very large amount of data in a relatively short period. Let's look at different data structures that are used in different situations

3. LINKED LIST:                         A Linked List is a linear data structure, in which the elements are not stored at contiguous memory locations. In simple words, a linked list consists of nodes where each node contains a data  Field and an address(link) of the next node in the list.

4. The capabilities of linked list: Dividing memory into a node. Each node have atleast one link field. To determine which nodes are in use which nodes are not in use or unused. To transfer the nodes from the reserved pool to the free pool. CREATE()              1. Procedure   CREATE(T)              2. call GETNODE(I)//get on available node//              3. T<---I ; DATA(I)<---'MAT'//store information into the node//              4. call GETNODE (I) //get a second available node//              5. LINK(I)<---0;DATA(I)<---'PAT'              6. End CREATE        

5.     INSERT()                1. Procedure INSERT(T,X)                2. call GETNODE(I)                3. DATA(I)<---'oat'                4. if T=0,then [T<--I];[LINK(1)<--0]                5. else[LINK(I)<--LINK(x)                6. LINK(x)<---I]                7. End INSERT       DELETE()                1. Procedure DELETE(x,y,T)                2. if y=0 then T<--LINK(T)//removes the first node//                3. else LINK(y)<--LINK(x)//removes an interior node//                4. call RET(x)//return node to storage pool//                5. End DELETE

6. Applications of linked list in computer science:

7. Applications of Linked lists in real world: The list of songs in the music player are linked to the previous and next songs. In a Web Browser, previous & next web page URLs are link through the previous & next buttons.(Spotify) In Image Viewer, the previous & next images are linked with the help of the previous & next buttons.(Gallery slideshow) In mobile phones, we save the contacts of the people. The newly entered contact details will be placed at the correct alphabetical order. This can be achieved by linked list to set contact at correct alphabetical position.

8. There are four types of linked lists: Singly linked list Doubly linked list Circular linked list Circular  doubly  linked list

9. SINGLY LINKED LIST:                       A Singly Linked List is a type of linked list that is unidirectional, that is it can be traversal in only one direction from head to the last node (tail)  , Each element in a linked list is called as a node . A single node contains data and an address the next node in the list. The first node is called the head ,which points to the first node of the list and helps us access every other element in the list . The last node also sometimes called the tail, to points NULL which helps us in determining when the list ends.    

10. DOUBLY LINKED LIST:                                     Doubly linked list contains a link element called first and last, Each link carries a data fields and Two link fields called as next and prev. Each link is linked with its next link using its next link. Each link is linked with its previous link using its previous link, following are the important points to be considered;        - Doubly linked list contains a link element called First&last.        - Each link carries a data field(s)&two link fields called next &prev.        - Each link is linked with its next link using its next link.        - Each link is linked with its previous link using its previous link.        - The last link carries a link as null to mark the end of the list.

11. Applications of   Doubly   Linked   lists in real world: Doubly linked lists are used in  previous and next page in a web browser- we can access the previous and next URL searched in a web browser by processing the back and next buttons since they are linked as a linked list. Music player-Songs in the music player are linked to the previous and next songs. It can be used in games like a deck of cards. It can be used to implement different tree data structures. It can be used to implement undo/redo operations. It is also used in constructing MRU/LRU(most/least recently used)cache.

12. CIRCULAR LINKED LIST:                           The circular linked list is a linked list where all nodes are connected to form a circle.  In a circular linked list,  the first node and the last the last node are connected to each other which forms a circle . There is no NULL at the end. Any node can be starting point ,We can traverse the whole  list by starting from any point . We just need to stop when the first visited node is visited again . Circular doubly linked list are used for the implementation of advanced data structures like the Fibonacci heap.

13. Applications of Circular Linked List: In real life it used on our personal computers ,where multiple applications are running. All the running applications are kept in a circular linked list and the OS gives a fixed slot to all for running. circular linked list can be used to organize multiple running applications on an operating system . These applications are iterated over by the OS. It is used by the OS to share time for different users, generally uses a Round-Robin time sharing mechanism. Multiplexer games are use a circular list to swap between players in a loop. The browser cache which allows you to hit the BACK button. Undo functionality in photoshop or word. Circular linked list used most recent list(MRU LIST).

14. CIRCULAR DOUBLY LINKED LIST:                             Circular doubly linked list has properties of both doubly linked list and circular linked list in which two consecutive elements are linked or connected elements are linked or connected by the previous and next pointer and the last node points to the first node by the next pointer and also the first node points to the last node by the previous pointer. A doubly circular linked list is a data structure that has properties of both circular linked list & doubly linked list . It is a list in which the last node of the list points to the start node, creating a loop.

15. Applications of Circular Doubly linked list: This Photo by Unknown author is licensed under CC BY .