Final Exam Data Structure course. No. of Branches (5)

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1 Page ١of 5 College Of Science and Technology Khan younis - Palestine Computer Science & Inf. Tech. Information Technology Data Structure (Theoretical Part) Time: 2 Hours Name: ID: Mark: Teacher 50 Mahmoud Rafeek Alfarra First Question No. of Branches (5) (0 min.) Write the pseudo code for the each of the following: In the following sorted array, Insert a new element with value 3 in its correct position (0/50) (0/0) array Detect the cell s index of the inserted elem. 2. From the back, Shift the elements to the right. 2 for ( int i = 0 ; i < arraylength; i++ ) if ( array[i]> 3 ) index = i break for ( int i = arraylength- ; i >index ; i-- ) b[ i- ] = b[ i ] b [index] = 3 In the following Linked List, Insert a new element with value 3 as the last node.. Create a pointer (Back) which will be pointed to the last node using loop for (Back=Head; Back.next!=null; Back= back.next); 2. new.next Points to null. 3. Back.next points to new. 4. size increments by one. 3 Write, how do we can search in the linked list using the id filed of the nodes. Create a pointer (current) which points to the First node (Head) Set a Boolean Flage to false for (current=head; current=null; current= current.next) if (current.id equals wanted) set flage to true if (flage equals to true) Print Exist Print does not exist

2 Page ٢of 5 4 Print all the element of the Stack. Create a pointer (current) which points to the last node (Top) for (current=top; current.next!=null; current= current.next) Print current.data 5 Peek the elements of the Queue If the front equals null Return null Return front Second Question No. of Branches (5) (30 min.) Answer the following question based on the requirements of each one. 2 (20/50) (20/20) In three points, discuss the difference between circular linked list and doubly linked list. (3 marks) Circular linked lists: Doubly linked list: The last node points to the first Each node points to not only node of the list. successor but the predecessor Check if the pointer of the current There are two NULL: at the first node is equal to the head to finish and last nodes in the list traversing the list. Advantage: given a node, it is One pointer easy to visit its predecessor. Convenient to traverse lists backwards Using the following Queue, perform the given operation using the linked list implementation of Queue and write the logic of enqueue and dequeue operations. (4 marks) Dequeue Logic: If front points to null print (the queue is empty) for (current = Rear; current.next!= Front; current = current.next) Front = current index-- size-- ) Add(Hussam) Ali, Mohamed, ghadeer, ahmad, hussam Enqueue Logic: Create new object If rear points to null rear= NewItem Front = NewItem NewItem.next = null NewItem.next = rear rear= NewItem size++ index++ 2) Delete() Mohamed, ghadeer, ahmad, hussam

3 Page ٣of 5 3) Delete() ghadeer, ahmad, hussam 4) Add(Hassan) ghadeer, ahmad, hussam, hassan 3 Discuss the concept of self-referential class. (2 marks) A self-referential class contains a reference class Node member that refers to an object of the same { class type. Class private int data; private Node next; Example a; public Node( int d ) { // } } Draw the displayed BST after perform the following operations : (4 marks) 4 Add the items (30, 5) Delete (0) Add 30: Add 5: Delete 0: Replace node 0 with node 5 using inorder successor 5 Discuss the main three concepts of Hashing. (3 marks) Hashing is a very common technique for storing data in such a way the data can be inserted and retrieved very quickly. Hashing uses a data structure called a hash table. To store an element in the hash table, the key is mapped into a number in the range of 0 to the hash table size using a function called a hash function. The ideal goal of the hash function is to store each key in its own cell in the array. Choosing a hash function depends on the data type of the key you are using. If your key is an integer, the simplest function is to return the key modulo the size of the array.

4 Page ٤of 5 Discuss the Traversing a Binary Search Tree methods with examples. 6 (6 marks) There are three traversal methods used with BSTs:. Inorder: visits all the nodes in a BST in ascending order of the node key values. (Example: lecture 4, slide2) 2. Preorder: visits the root node first, followed by the nodes in the subtrees under the left child of the root, followed by the nodes in the subtrees under the right child of the root. (Example: lecture 4, slide5) 3. Postorder: visits nodes and process it as shown. (Example: lecture 4, slide7) Third Question No. of Branches (2) (0/50) (5 min.) Branch(A) (5/0) State whether each of the following is true[t]or false [F].If false,explain why? In a stack, the first item to be added, is the last item to be removed. T 2 Queue nodes are stored contiguously in memory. F Queue nodes are stored dynamically in memory. (OR) k Array nodes are stored contiguously in memory. k 3 The primary operations of the stack data structure are enqueue and dequeue. The primary operations of the stack data structure are Pop and Push. k 4 Recursion is a control structure that uses repetition. F Recursion is a control structure that uses selection.k 5 The Console.WriteLine(*ptr), Displays the value of the memory address F T (0 min.) Branch(B) (5/0) Using the displayed words, Fill in the blanks five of the following statements: Key ordered unordered Cell value static binary - leaf parent length depth doubly The ideal goal of the hash function is to store each Key in its own cell in the array. 2 A graph whose pairs are ordered is called a digraph. 3 A doubly linked list is convenient for applications that move more than once through a list. 4 Arrays are static entities, in that they remain the same size once they are

5 Page ٥of 5 created. 6 The node immediately above a specified node called parent 7 The number of nodes in longest path from root to leaf is the depth Fourth Question No. of Branches (2) (30 min.) Solve the following questions:. Using Graph data structure to represent the following sentences and then note the following Type of graph: digraph Example of leaf: day Example of Parent: Palestine Path from Palestine and day: 0 The sentences are: Palestine freedom requires all Muslims. All Muslims must pray five times every day. Freedom for Palestine Draw the graph with nodes, each one is a word in its specific order. (0/50) (0/0) 2. Write a program that uses a stack to determine whether a string is a palindrome (i.e., the string is spelled identically backward and forward). The program should ignore spaces and punctuation. Hint: ABCCBA is a palindrome CDERRCDEC is not a palindrome Using the main operations of stack which are Push and Pop. Push all the letters of string in stack. 2. Pop the first half of stack into stack2. 3. Pop one from stack and one from stack2, if they are equals continue else stop. 4. while the poped letters are equals continue and if one of stacks are empty before other stop (not pland.) With My best Wishes Mahmoud Rafeek Alfarra