PROGRAMMING AND DATA STRUCTURE TWO MARKS

       

UNIT-I

LINEAR STRUCTURE

1.Write down the definition of data structures?

A data structure is a mathematical or logical way of organizing data in the

memory that consider not only the items stored but also the relationship to eachother and

also it is characterized by accessing functions.

2.What is meant by problem solving?

Problem solving is a creative process, which needs systemization and

mechanization.

3. Give few examples for data structures?

Stacks, Queue, Linked list, Trees, graphs

4. What is problem definition phase?

The first step in solving a problem is to understand problem clearly. Hence,

the first phase is the problem definition phase. That is, to extract the task from the

problem statement. If the problem is not understood, then the solution will not be correct

and it may result in wastage of time and effort.

5. Define Algorithm?

Algorithm is a solution to a problem independent of programming

language. It consist of set of finite steps which, when carried out for a given set of

inputs, produce the corresponding output and terminate in a finite time.

6. Define Program?

Set of instructions to find the solution to a problem. It is expressed in a

programming language in an explicit and unambiguous manner.

7. Mention how similarities among the problems are used in problem solving?

This method is used to find out if a problem of this sort has been already

solved and to adopt a similar method in solving the problem. The contribution of

experience in the previous problem with help and enhance the method of problem for the

current problem.

8. What is working backward from the solution?

When we have a solution to the problem then we have to work backward to

find the starting condition. Even a guess can take us to the starting of the problem. This is

very important to sytematize the investigation to avoid duplication of our effort.

9. Mention some of the problem solving strategies?

• The most widely strategies are listed below

• Divide and conquer

• Binary doubling strategy

• Dynamic programming

10. What is divide and conquer method?

The basic idea is to divide the problem into several sub problems beyond

which cannot be further subdivided. Then solve the sub problems efficiently and

join then together to get the solution for the main problem.

11. What are the features of an efficient algorithm?

• Free of ambiguity

• Efficient in execution time

• Concise and compact

• Completeness

• Definiteness

• Finiteness

12. List down any four applications of data structures?

• Compiler design

• Operating System

• Database Management system

• Network analysis

13. What is binary doubling strategy?

The reverse of binary doubling strategy, i.e. combining small problems in to one

is known as binary doubling strategy. This strategy is used to avoid the

generation of intermediate results.

14. Where is dynamic programming used?

Dynamic programming is used when the problem is to be solved in a

sequence of intermediate steps. It is particularly relevant for many optimization

problems, i.e. frequently encountered in Operations research.

15. Define top-down design?

Top-down design is a strategy that can be applied to find a solution to a

problem from a vague outline to precisely define the algorithm and program

implementation by stepwise refinement.

16. Mention the types of bugs that may arise in a program?

The different types of bugs that can arise in a program are

• Syntactic error

• Semantic error

• Logical error

17. What is program testing?

Program testing is process to ensure that a program solves the smallest

possible problem, when all the variables have the same value, the biggest possible

problem, unusual cases etc.

18. What is program verification?

Program verification refers to the application of mathematical proof

techniques, to verify that the results obtained by the execution of the program with

arbitrary inputs are in accord with formally defined output Specifications.

19. How will you verify branches with segments?

To handle the branches that appear in the program segments, it is necessary to setup

and proves verification conditions individually.

20.What is proof of termination?

To prove that a program accomplishes its stated objective in a finite number of

steps is called program termini nation. The prooft of termination is obtained directly from

the properties of the interactive constructs.

21. List out the areas in which data structures are applied extensively?

Compiler Design,

Operating System,

Database Management System,

Statistical analysis package,

Numerical Analysis,

Graphics,

Artificial Intelligence,

Simulation

22. What are the major data structures used in the following areas : RDBMS,

Network data model & Hierarchical data model.

RDBMS – Array (i.e. Array of structures)

Network data model – Graph

Hierarchical data model – Trees

23. If you are using C language to implement the heterogeneous linked list, what

pointer type will you use?

The heterogeneous linked list contains different data types in its nodes and we need a

link, pointer to connect them. It is not possible to use ordinary pointers for this. So we go

for void pointer. Void pointer is capable of storing pointer to any type as it is a generic

pointer type.

24. Minimum number of queues needed to implement the priority queue?

Two. One queue is used for actual storing of data and another for storing

priorities.

25. What is the data structures used to perform recursion?

Stack. Because of its LIFO (Last In First Out) property it remembers its ‘caller’ so knows whom to return when the function has to return. Recursion makes use of system

stack for storing the return addresses of the function calls.

Every recursive function has its equivalent iterative (non-recursive) function. Even when

such equivalent iterative procedures are written, explicit stack is to be used.

UNIT –II

TREE STRUCTURE

1.What is meant by an abstract data type?

An ADT is a set of operation. Abstract data types are mathematical

abstractions.Eg.Objects such as list, set and graph along their operations can be

viewed as ADT's.

2. What are the operations of ADT?

Union, Intersection, size, complement and find are the various operations of

ADT.

3. What is meant by list ADT?

List ADT is a sequential storage structure. General list of the form a1, a2,

a3.…., an and the size of the list is 'n'. Any element in the list at the position I is

defined to be ai, ai+1 the successor of ai and ai-1 is the predecessor of ai.

4. What are the various operations done under list ADT?

• Print list

• Insert

• Make empty

• Remove

• Next

• Previous

• Find kth

5. What are the different ways to implement list?

• Simple array implementation of list

• Linked list implementation of list

6. What are the advantages in the array implementation of list?

a) Print list operation can be carried out at the linear time

b) Fint Kth operation takes a constant time

7. What is a linked list?

Linked list is a kind of series of data structures, which are not necessarily

adjacent in memory. Each structure contain the element and a pointer to a record containing its successor.

8. What is a pointer?

Pointer is a variable, which stores the address of the next element in the

list.Pointer is basically a number.

9. What is a doubly linked list?

In a simple linked list, there will be one pointer named as 'NEXT

POINTER' to point the next element, where as in a doubly linked list, there will be

two pointers one to point the next element and the other to point the previous

element location.

10. Define double circularly linked list?

In a doubly linked list, if the last node or pointer of the list, point to the first

element of the list, then it is a circularly linked list.

11. What is the need for the header?

Header of the linked list is the first element in the list and it stores the

number of elements in the list. It points to the first data element of the list.

12. List three examples that uses linked list?

• Polynomial ADT

• Radix sort

• Multi lists

13. Give some examples for linear data structures?

• Stack

• Queue

14. What is a stack?

Stack is a data structure in which both insertion and deletion occur at one

end only. Stack is maintained with a single pointer to the top of the list of

elements. The other name of stack is Last-in -First-out list.

15. Write postfix from of the expression –A+B-C+D?

A-B+C-D+

16. How do you test for an empty queue?

To test for an empty queue, we have to check whether READ=HEAD

where REAR is a pointer pointing to the last node in a queue and HEAD is a pointer that pointer to the dummy header. In the case of array implementation of

queue, the condition to be checked for an empty queue is READ<FRONT.

17.What are the postfix and prefix forms of the expression?

A+B*(C-D)/(P-R)

Postfix form: ABCD-*PR-/+

Prefix form: +A/*B-CD-PR

18. Explain the usage of stack in recursive algorithm implementation?

In recursive algorithms, stack data structures is used to store the return

address when a recursive call is Encountered and also to store the values of all the

parameters essential to the current state of the procedure.

19. Write down the operations that can be done with queue data structure?

Queue is a first - in -first out list. The operations that can be done with

queue are addition and deletion.

20. What is a circular queue?

The queue, which wraps around upon reaching the end of the array is called as

circular queue.

21. What are the notations used in Evaluation of Arithmetic Expressions using

prefix and postfix forms?

Polish and Reverse Polish notations.

22. Convert the expression ((A + B) * C – (D – E) ^ (F + G)) to equivalent Prefix and

Postfix notations.

Prefix Notation:

^ - * +ABC - DE + FG Postfix Notation:

AB + C * DE - - FG + ^

23. Sorting is not possible by using which of the following methods?

(a) Insertion

(b) Selection

(c) Exchange

(d) Deletion

(d) Deletion.

Using insertion we can perform insertion sort, using selection we can perform selection

sort, using exchange we can perform the bubble sort (and other similar sorting methods).

But no sorting method can be done just using deletion.

24. A binary tree with 20 nodes has null branches?

21

Let us take a tree with 5 nodes (n=5)

It will have only 6 (ie,5+1) null branches. In general,

A binary tree with n nodes has exactly n+1 null nodes.

25. What are the methods available in storing sequential files ?

Straight merging,

Natural merging,

Polyphase sort,

Distribution of Initial runs.

UNIT-III

BALANCED SEARCH TREES AND INDEXING

1. Define non-linear data structure

Data structure which is capable of expressing more complex relationship

than that of physical adjacency is called non-linear data structure.

2. Define tree?

A tree is a data structure, which represents hierarchical relationship between

individual data items.

3. Define leaf?

In a directed tree any node which has out degree o is called a terminal node or a

leaf.

4. What is meant by directed tree?

Directed tree is an acyclic diagraph which has one node called its root with

in degree o while all other nodes have in degree I.

5. What is a ordered tree?

In a directed tree if the ordering of the nodes at each level is prescribed then such

a tree is called ordered tree.

6. What are the applications of binary tree?

Binary tree is used in data processing.

a. File index schemes

b. Hierarchical database management system

7. What is meant by traversing?

Traversing a tree means processing it in such a way, that each node is

visited only once.

8. What are the different types of traversing?

The different types of traversing are

a. Pre-order traversal-yields prefix from of expression.

b. In-order traversal-yields infix form of expression.

c. Post-order traversal-yields postfix from of expression.

9. What are the two methods of binary tree implementation?

Two methods to implement a binary tree are,

a. Linear representation.

b. Linked representation

10. Define pre-order traversal?

Pre-order traversal entails the following steps;

a. Process the root node

b. Process the left subtree

c. Process the right subtree

11.Define post-order traversal?

Post order traversal entails the following steps;

a. Process the left subtree

b. Process the right subtree

c. Process the root node

12. Define in -order traversal?

In-order traversal entails the following steps;

a. Process the left subtree

b. Process the root node

c. Process the right subtree

13. What is a balance factor in AVL trees?

Balance factor of a node is defined to be the difference between the height

of the node's left subtree and the height of the node's right subtree.

14. What is meant by pivot node?

The node to be inserted travel down the appropriate branch track along the way of

the deepest level node on the branch that has a balance factor of +1 or -1 is called pivot

node.

15. What is the length of the path in a tree?

The length of the path is the number of edges on the path. In a tree there is exactly

one path form the root to each node.

16. Define expression trees?

The leaves of an expression tree are operands such as constants or variable names

and the other nodes contain operators.

17. What is the need for hashing?

Hashing is used to perform insertions, deletions and find in constant

average time.

18. Define hash function?

Hash function takes an identifier and computes the address of that identifier in the

hash table using some function.

19. List out the different types of hashing functions?

The different types of hashing functions are,

a. The division method

b. The mind square method

c. The folding method

d. Multiplicative hashing

e. Digit analysic

20. What are the problems in hashing?

a. Collision

b. Overflow

When two keys compute in to the same location or address in the hash table

through any of the hashing function then it is termed collision.

21. How many different trees are possible with 10 nodes ?

1014

For example, consider a tree with 3 nodes(n=3), it will have the maximum combination

of 5 different (ie, 23 - 3 = 5) trees.

In general:

If there are n nodes, there exist 2n-n different trees.

22. List out few of the Application of tree data-structure?

The manipulation of Arithmetic expression,

Symbol Table construction,

Syntax analysis.

23. List out few of the applications that make use of Multilinked Structures?

Sparse matrix,

Index generation.

24. In tree construction which is the suitable efficient data structure?

(a) Array (b) Linked list (c) Stack (d) Queue (e) none

(b) Linked list

25. What is the type of the algorithm used in solving the 8 Queens problem?

Backtracking.

UNIT-IV

GRAPHS

1. What is meant by sorting?

Ordering the data in an increasing or decreasing fashion according to some

relationship among the data item is called sorting.

2. What are the two main classifications of sorting based on the source of data?

• Internal sorting

• External sorting

3. What is meant by external sorting?

External sorting is a process of sorting in which large blocks of data stored

in storage devices are moved to the main memory and then sorted.

4. What is meant by internal sorting?

Internal sorting is a process of sorting the data in the main memory.

5. What are the various factors to be considered in deciding a sorting algorithm?

• Programming time

• Execution time of the program

• Memory needed for program environment

6. What is the main idea behind insertion sort?

The main idea of insertion sort is to insert in the i th pass the i th element in

A (1) A (2)...A (i) in its rightful place.

7. What is the main idea behind insertion sort?

The main idea behind the selection sort is to find the smallest element

among in A (I) A (J+1)...A (n) and then interchange it with a (J). This process is

then repeated for each value of J.

8. What is the basic of shell sort?

Instead of sorting the entire array at once, it is first divide the array into

smaller segments, which are then separately sorted using the insertion sort.

9. What is the other name for shell sort?

Diminishing increment sort.

10. What is the purpose of quick sort?

The purpose of the quick sort is to move a data item in the correct direction, just

enough for to reach its final place in the array.

11. What i the advantage of quick sort?

Quick sort reduces unnecessary swaps and moves an item to a greater

distance, in one move.

12. What is the average efficiency of heap sort?

The average efficiency of heap sort is 0 (n(log2 n)) where, n is the number

of elements sorted.

13. Define segment?

When large blocks of data are to be sorted, only a portion of the block or

file is loaded in the main memory of the computer since, it cannot hold the entire

block. This small portion of file is called a segment.

14. Name some of the external sorting methods?

• Polyphase merging

• Oscillation sorting

• Merge sorting

15. When is a sorting method said to be stable?

A sorting method is said to be stable, it two data items of matching values

are guaranteed to be not rearranged with respect to each other as the algorithm

progresses.

16. Name some simple algorithms used in external sorting?

• Multiway merge

• Polyphase merge

• Replacement selection

17. When can we use insertion sort?

Insertion sort is useful only for small files or very nearly sorted files.

18. How many passes are required fork-way merging?

The number of passes required using k-way merging is [log k (n/m)]

because the N H S get k times as large in each pass.

19. Define max heap?

A heap in which the parent has a larger key than the child's is called a max heap.

20. Define min heap?

A heap in which the parent has a smaller key than the child's is called a min

heap.

21. In an AVL tree, at what condition the balancing is to be done?

If the ‘pivotal value’ (or the ‘Height factor’) is greater than 1 or less than –1.

22. What is the bucket size, when the overlapping and collision occur at same time?

One. If there is only one entry possible in the bucket, when the collision occurs, there is

no way to accommodate the colliding value. This results in the overlapping of values.

23. Traverse the given tree using Inorder, Preorder and Postorder traversa

Inorder : D H B E A F C I G J

Preorder: A B D H E C F G I J

Postorder: H D E B F I J G C A

24. There are 8, 15, 13, 14 nodes were there in 4 different trees. Which of them could

have formed a full binary tree?

15.

In general:

There are 2n-1 nodes in a full binary tree.

By the method of elimination:

Full binary trees contain odd number of nodes. So there cannot be full binary trees with 8

or 14 nodes, so rejected. With 13 nodes you can form a complete binary tree but not a full

binary tree. So the correct answer is 15.

Note:

Full and Complete binary trees are different. All full binary trees are complete binary

trees but not vice versa.

25. In the given binary tree, using array you can store the node 4 at which location?

At location 6

1 2 3 - - 4 - - 5

Root LC1 RC1 LC2 RC2 LC3 RC3 LC4 RC4

where LCn means Left Child of node n and RCn means Right Child of node n.

UNIT-V

ALGORITHM DESIGN AND ANALYSIS

1.Define Graph?

A graph G consist of a nonempty set V which is a set of nodes of the graph, a set

E which is the set of edges of the graph, and a mapping from the set for edge E to a set of

pairs of elements of V. It can also be represented as G=(V, E).

2. Define adjacent nodes?

Any two nodes which are connected by an edge in a graph are called

adjacent nodes. For example, if and edge xÎE is associated with a pair of nodes

(u,v) where u, v Î V, then we say that the edge x connects the nodes u and v.

3. What is a directed graph?

A graph in which every edge is directed is called a directed graph.

4. What is a undirected graph?

A graph in which every edge is undirected is called a directed graph.

5. What is a loop?

An edge of a graph which connects to itself is called a loop or sling.

6.What is a simple graph?

A simple graph is a graph, which has not more than one edge between a

pair of nodes than such a graph is called a simple graph.

7. What is a weighted graph?

A graph in which weights are assigned to every edge is called a weighted

graph.

8. Define out degree of a graph?

In a directed graph, for any node v, the number of edges which have v as

their initial node is called the out degree of the node v.

9. Define indegree of a graph?

In a directed graph, for any node v, the number of edges which have v as

their terminal node is called the indegree of the node v.

10. Define path in a graph?

The path in a graph is the route taken to reach terminal node from a starting node.

11. What is a simple path?

A path in a diagram in which the edges are distinct is called a simple path.

It is also called as edge simple.

12. What is a cycle or a circuit?

A path which originates and ends in the same node is called a cycle or

circuit.

13. What is an acyclic graph?

A simple diagram which does not have any cycles is called an acyclic

graph.

14. What is meant by strongly connected in a graph?

An undirected graph is connected, if there is a path from every vertex to

every other vertex. A directed graph with this property is called strongly

connected.

15. When is a graph said to be weakly connected?

When a directed graph is not strongly connected but the underlying graph is

connected, then the graph is said to be weakly connected.

16. Name the different ways of representing a graph?

• Adjacency matrix

• Adjacency list

17. What is an undirected acyclic graph?

When every edge in an acyclic graph is undirected, it is called an undirected

acyclic graph. It is also called as undirected forest.

18. What are the two traversal strategies used in traversing a graph?

Breadth first search

Depth first search

19. What is a minimum spanning tree?

A minimum spanning tree of an undirected graph G is a tree formed from

graph edges that connects all the vertices of G at the lowest total cost.

20. What is NP?

NP is the class of decision problems for which a given proposed solution

for a given input can be checked quickly to see if it is really a solution.

21. Sort the given values using Quick Sort?

65 70 75 80 85 60 55 50 45

Sorting takes place from the pivot value, which is the first value of the given elements,

this is marked bold. The values at the left pointer and right pointer are indicated using L

and R respectively.

65 70L 75 80 85 60 55 50 45R

Since pivot is not yet changed the same process is continued after interchanging the

values at L and R positions

65 45 75 L 80 85 60 55 50 R 70

65 45 50 80 L 85 60 55 R 75 70

65 45 50 55 85 L 60 R 80 75 70

65 45 50 55 60 R 85 L 80 75 70

When the L and R pointers cross each other the pivot value is interchanged with the value

at right pointer. If the pivot is changed it means that the pivot has occupied its original

position in the sorted order (shown in bold italics) and hence two different arrays are

formed, one from start of the original array to the pivot position-1 and the other from

pivot position+1 to end.

60 L 45 50 55 R 65 85 L 80 75 70 R

55 L 45 50 R 60 65 70 R 80 L 75 85

50 L 45 R 55 60 65 70 80 L 75 R 85

In the next pass we get the sorted form of the array.

45 50 55 60 65 70 75 80 85

22. For the given graph, draw the DFS and BFS?

BFS: A X G H P E M Y J

DFS: A X H P E Y M J G

23. Classify the Hashing Functions based on the various methods by which the key

value is found.

Direct method,

Subtraction method,

Modulo-Division method,

Digit-Extraction method,

Mid-Square method,

Folding method,

Pseudo-random method.

24. What are the types of Collision Resolution Techniques and the methods used in

each of the type?

Open addressing (closed hashing),

The methods used include:

Overflow block, Closed addressing (open hashing)

The methods used include:Linked list,Binary tree…

25. In RDBMS, what is the efficient data structure used in the internal storage

representation?

B+ tree. Because in B+ tree, all the data is stored only in leaf nodes, that makes searching

easier. This corresponds to the records that shall be stored in leaf nodes.