AJK PSC Lecturer Computer Science Past paper held 1st April 2026

Azad Jammu & Kashmir Public Service Commission, Muzaffarabad
Post Name: Lecturer Computer Science (BS-17)
Total Marks: 100
Time Allowed: 100 Minutes
Note: Fill the correct answers on the OMR sheet.

100 min
Score: 0
Attempted: 0/100

1. In a linked list, there are no NULL links in:
(A) Single linked list
(B) Linear doubly linked list
(C) Circular linked list
(D) None of the above

2. In a stack, the command to access the nth element from the top of the stack is:
(A) S[Top + n]
(C) None of the above
(B) S[Top + n]+ 1]
(D) S[Top – n

3. What is the time complexity of binary search tree (BST) (best, worst)?
(A) N, N+1
(B) log N, N
(C) 1, log N
(D) None of the above

4. Which of the following algorithms swaps adjacent entries?
(A) Insertion sort
(B) Bubble sort
(C) Shell sort
(D) Quick sort

5. What does O(n) mean?
(A) n nested loops
(B) n times slower
(C) Time proportional to n
(D) n statements

6. BFS uses:
(A) Queue
(B) Linked list
(C) Graph
(D) Stack

7. Which of the following is not a linear data structure?
(A) Array
(B) Linked List
(C) None of the above
(D) Both a & b

8. Evaluate the prefix expression: * / b + - d a c (a=3, b=6, c=1, d=5)
(A) 10
(B) 5
(C) 0
(D) 15

9. Prim’s algorithm is based on:
(A) Divide and conquer
(B) Dynamic programming
(C) Greedy method
(D) Branch and bound

10. The physical layer is concerned with:
(A) Port to port delivery
(B) Process to process delivery
(C) Application to application delivery
(D) Bit-by-bit delivery

11. Time sharing is best suited for transmission of data in:
(A) Simplex mode
(B) Half duplex mode
(C) Full duplex mode
(D) None of the above

12. A coaxial cable has conductors with ________
(A) None of the above
(B) Equal resistance
(C) The same diameter
(D) A common axis

13. The area of coverage of a satellite radio beam is called its ________
(A) Beam width
(B) Circular polarization
(C) Footprint
(D) None of the above

14. Buffering is the process of ________
(A) A method for reducing routing overhead
(B) A method for reducing cross talk
(C) Temporarily storing data to allow for small variations in device speed
(D) None of the above

15. Which of the following is not applicable for IP protocol?
(A) Connectionless
(B) Offers reliable service
(C) Offers unreliable service
(D) None of the above

16. Which field helps to check rearrangement of fragments?
(A) Identifier
(B) Flag
(C) TTL
(D) Offset

17. In asymmetric key cryptography, the private key is held by
(A) Sender
(B) All devices connected to the network
(C) Both sender and receiver
(D) Receiver

18. When was the first operating system developed?
(A) 1949
(B) 1948
(C) 1950
(D) 1951

19. In a time-sharing operating system, when the time slot given to a process is completed, the process goes from running state to
(A) Suspended state
(B) Blocked state
(C) Ready state
(D) Terminated state

20. Which one of the following is a synchronization tool?
(A) Thread
(B) Semaphore
(C) Pipe
(D) Socket

21. Operating system maintains the page table for
(A) Each instruction
(B) Each thread
(C) Each process
(D) Each address

22. Because of the concept of virtual memory, the memory can be shared among
(A) None of the above
(B) Data
(C) Instructions
(D) Processes

23. Which one of the following address is generated by a CPU?
(A) Physical address
(B) Logical address
(C) Absolute address
(D) None of the above

24. Memory fragmentation results in
(A) Stack overflow
(B) Page faults
(C) Poor memory utilization
(D) Better memory utilization

25. An edge from process Pi to process Pj in a wait-for graph implies that
(A) Process Pj is waiting for a resource held by process Pi
(B) Process Pi is waiting for a resource held by process Pj
(C) Process Pi is waiting for a resource held by process Pi
(D) None of the above

26. Which of the following is the feature of a good software?
(A) Modularity
(B) Accessibility
(C) All of these
(D) Portability

27. CASE stands for
(A) Computer Assisted Software Engineering
(B) Computer Aided Software Engineering
(C) Computer Adaptive Software Engineering
(D) None of the above

28. The activity that distributes estimated effort across the planned project duration by allocating the effort to specific software engineering tasks is called
(A) Project scheduling
(B) Project tracking
(C) Project milestone
(D) None of the above

29. Which of the following is part of the manifesto for agile software development?
(A) Customer collaboration
(B) Individuals and interactions
(C) All of the above
(D) Working software

30. Which of the following document contains the user system requirements?
(A) SRS
(B) STD
(C) SRD
(D) SDD

31. In UML, a domain model is built after
(A) Design class diagram
(B) None of the above
(C) System sequence diagrams
(D) Interaction diagrams

32. The include relationship in a use case diagram captures
(A) Optional behaviour
(B) Mandatory behaviour
(C) Tertiary behaviour
(D) System behaviour

33. Which one of the following is not part of a UML design class diagram?
(A) Class name
(B) None of the above
(C) Class functions
(D) Class attributes

34. Aggregation is a type of relationship in which
(A) A child class can exist independently of the parent class
(B) A child class cannot exist independently of the parent class
(C) A parent class is dependent on the child class
(D) None of the above

35. The circuit used to store one bit of data is known as
(A) Register
(B) Flip-flop
(C) Encoder
(D) Decoder

36. Which of the following code used in present day computing was developed by IBM?
(A) ASCII
(B) Hollerith Code
(C) None of the above
(D) EBCDIC Code

37. Memory access in RISC architecture is limited to instructions
(A) STA and LDA
(B) PUSH and POP
(C) CALL and RET
(D) MOV and JMP

38. A collection of lines that connects several devices is called
(A) Peripheral connection wires
(B) Bus
(C) Both a & b
(D) None of the above

39. A program counter (PC) is also called
(A) Instruction pointer
(B) Data pointer
(C) Memory pointer
(D) None of the above

40. In Assembly language programming, the minimum number of operands required by an instruction is/are
(A) Zero
(B) One
(C) Two
(D) Both b & c

41. A nibble is a group of ______ bits
(A) 4
(B) 2
(C) 8
(D) 16

42. In a vectored Interrupt
(A) The branch address is assigned to a fixed location in memory
(B) The interrupting source supplies the branch information to the processor through an interrupt vector
(C) The branch address is obtained from a register in the processor
(D) None of the above

43. A computer network permits sharing of
(A) Resources
(B) Both a & b
(C) Information
(D) None of the above

44. ATM stands for
(A) Automated teller machine
(B) Automatic teller machine
(C) Automatic take money
(D) None of the above

45. ATM networks are
(A) Connectionless
(B) Satellite based
(C) Connection oriented
(D) None of the above

46. DHCP stands for
(A) Dynamic Host Configuration Protocol
(B) Digital Host Communication Provider
(C) Dynamic High Computing Processor
(D) Digital Host Communication Protocol

47. To deliver a message to the correct application program running on a host, the ______ address must be consulted
(A) Physical
(B) IP
(C) Port
(D) Tunnel

48. What is the main purpose of a data link layer?
(A) Requests network services
(B) Encryption
(C) Adds physical addresses (MAC addresses)
(D) Establishes communication sessions

49. IPv6 uses ______ bit addresses
(A) 32
(B) 64
(C) 128
(D) 256

50. Session layer checkpoints
(A) Control the addition of headers
(B) Allow just a portion of a file to be resent
(C) Detect and recover errors
(D) Are involved in dialog control

51. Power set of empty set has exactly ______ subset
(A) Zero
(B) Two
(C) One
(D) None of the above

52. For an inverse to exist it is necessary that a function be a
(A) Bijection
(B) Injection
(C) Surjection
(D) None of the above

53. Which of the following can only be used in disproving statements?
(A) Direct proof
(B) Contrapositive proof
(C) Mathematical induction
(D) Counterexample

54. Which one of the following is a proposition?
(A) Get me a glass of milk
(B) The only odd prime number is 2
(C) What time is it now?
(D) God bless you

55. How many bit strings of length 4 contain two zeros and two ones
(A) 4
(B) 5
(C) 2
(D) 6

56. Let P and Q be two logical statements then P → Q is logically equivalent to
(A) ¬P ∧ Q
(B) ¬P ∨ Q
(C) ¬P ∧ ¬Q
(D) P ∨ Q

57. Two sets are called disjoint if their ______ is empty
(A) Intersection
(B) Union
(C) Power set
(D) Cartesian product

58. Let P(x) denote the statement x > 7 then which of these has truth value true?
(A) P(1)
(B) P(9)
(C) P(2)
(D) P(7)

59. HTML is what type of language?
(A) Scripting language
(B) Markup language
(C) Programming language
(D) Protocol

60. Fundamental HTML block is known as
(A) HTML element
(B) HTML tag
(C) HTML attribute
(D) HTML body

61. What is a CMS in web design?
(A) Content mixing system
(B) Creative management system
(C) Content management system
(D) Creative managerial system

62. Which protocol is used for WWW?
(A) SMTP
(B) HTTP
(C) TCP
(D) FTP

63. A web cookie is
(A) Sent from root server to all servers
(B) Sent from browser to server and stored there
(C) Sent from website and stored in browser
(D) None of the above

64. ______ is an FTP search tool
(A) Google
(B) AltaVista
(C) Archie
(D) Gopher

65. An email message is broken into
(A) Packets
(B) Frames
(C) Bytes
(D) Hyper text

66. Which is the correct HTML tag for inserting a line break?
(A) (B)
(C)
(D)

67. The operator % in C language is known as
(A) Percentage operator
(B) Quotient operator
(C) Division operator
(D) Modulus operator

68. Which is correct array initialization in C?
(A) int a(3) = {1,2,3};
(B) int a = {1,2,3};
(C) int a new int[3];
(D) int a[3] = {1,2,3};

69. What will be the output of the following code? (sum of array 1,2,3,4)
(A) 10
(B) 1
(C) 12
(D) 20

70. What will be the output of the expression 2 + 4/2 + 6*2
(A) 12
(B) 15
(C) 18
(D) 16

71. How can you access the third element of an array using pointer notation?
(A) a+3
(B) &a+3
(C) *a+3
(D) *(a+2)

72. The declaration int x:8 indicates
(A) That x is an 8-bit integer
(B) That x stores a value of 8
(C) Both a & b
(D) None of the above

73. The printf(“Hello”) returns
(A) 10
(B) 1
(C) 5
(D) 0

74. What will be the output of the following code?
(A) 12
(B) 18
(C) 16
(D) 14

75. Constructor has
(A) Void return type
(B) Class object
(C) No return type
(D) None of the above

76. Objects are created using new operator at
(A) None of the above
(B) Compile time
(C) Both
(D) Run time

77. The relationship between a base class and derived class is known as
(A) Inheritance
(B) Polymorphism
(C) Abstraction
(D) Encapsulation

78. Which function is inherited from base class?
(A) None of the above
(B) Destructor
(C) Static function
(D) Constructor

79. Which operator is used to access class members?
(A) Dot operator
(B) Arrow operator
(C) Both a & b
(D) Direct access

80. Virtual functions are primarily defined in
(A) None of the above
(B) Derived class
(C) Both
(D) Base class

81. A virtual function should be
(A) Private
(B) Public
(C) Protected
(D) Default

82. Which function is used for dynamic memory allocation?
(A) malloc
(B) calloc
(C) None of the above
(D) Both a & b

83. Late binding is implemented using
(A) Friend function
(B) Static function
(C) Virtual function
(D) None of the above

84. Which of the following is not a backtracking algorithm?
(A) M-coloring problem
(B) N-queen problem
(C) Tower of Hanoi
(D) Knight tour problem

85. The number of nodes in a full k-ary tree with n internal nodes is
(A) nk
(B) (n-1)k+1
(C) n(k-1)+1
(D) n(k-1)

86. The time complexity of Floyd-Warshall algorithm is
(A) O(n²logn)
(B) O(n³)
(C) O(nlogn)
(D) O(n²)

87. Which of the following is a key characteristic of Dynamic Programming?
(A) It solves problems by dividing them into independent subproblems
(B) It always uses recursion only
(C) It solves problems by combining solutions of overlapping subproblems
(D) It does not store intermediate results

88. Quick sort comparisons
(A) C1 > C2
(B) C1 < C2
(C) C1 = C2
(D) None of the above

89. Merge sort follows
(A) Divide and conquer
(B) Backtracking
(C) Dynamic programming
(D) Greedy method

90. Prefix expression of A + (B - C) * D is
(A) + A * B C D
(B) + A * - B C D
(C) ABC - D * +
(D) None of the above

91. Majority element can be found in
(A) O(1)
(B) O(log n)
(C) O(n²)
(D) O(n)

92. Minimum operations to evaluate polynomial
(A) 3
(B) 7
(C) 8
(D) 6

93. Set concept is used in
(A) None of the above
(B) Hierarchical model
(C) both b and c
(D) Relational model

94. Relational algebra is
(A) DDL
(B) None of the above
(C) Meta language
(D) Procedural query language

95. In a relation
(A) Both a & b
(B) No duplicate rows
(C) Ordering of tuples is immaterial
(D) None of the above

96. Derived attributes in ER diagram are represented by
(A) Dashed ellipse
(B) Ellipse
(C) Rectangle
(D) Triangle

97. Distinct A including NULL is
(A) Candidate key
(B) Not a candidate key
(C) Primary key
(D) Both a & c

98. Which is not true for a view?
(A) It is derived from base table
(B) It is stored permanently
(C) It is a virtual table
(D) It may not have derived columns

99. Which SQL command is used to delete a column?
(A) UPDATE
(B) ALTER
(C) DELETE
(D) DROP

100. Operation used for selecting columns in relational algebra is
(A) Selection
(B) Projection
(C) Union
(D) Join