Q4➡| Algorithms Which one of the following is the recurrence equation for the worst case time complexity of the Quicksort algorithm for sorting n(≥ 2) numbers? In the recurrence equations given in the options below, c is a constant.
Q5➡| Data Structure The height of a tree is the length of the longest root-to-leaf path in it. The maximum and minimum number of nodes in a binary tree of height 5 are
Q12➡| Computer Organization For computers based on three-address instruction formats, each address field can be used to specify which of the following: (S1) A memory operand (S2) A processor register (S3) An implied accumulator register
Q13➡| Computer Network Suppose two hosts use a TCP connection to transfer a large file. Which of the following statements is/are False with respect to the TCP connection?
I. If the sequence number of a segment is m, then the sequence number of the subsequent segment is always m+1. II. If the estimated round trip time at any given point of time is t sec, the value of the retransmission timeout is always set to greater than or equal to t sec. III. The size of the advertised window never changes during the course of the TCP connection. IV. The number of unacknowledged bytes at the sender is always less than or equal to the advertised window.
i ➥ III only
ii ➥ I and III only
iii ➥ I and IV only
iv ➥ II and IV only
Show Answer With Best Explanation
Answer: II
Explanation: Statement(I): If the sequence number of a segment is m, then the sequence number of the subsequent segment is always m+1.(False) 1 Byte of Data consumes 1 Sequence number.If Sequence number of segment is m, then the Sequence number of subsequent segment is m+1,only if 1 Byte of Data is transferred. But it is already given that Host transfer karge file. So, the statement is False.
Statement(II): If the estimated round trip time at any given point of time is t sec, the value of the retransmission timeout is always set to greater than or equal to t sec.(True) TCP sets a timeout when it sends Data and if Data is not acknowledged before timeout expires it retransmit data. Timeout is based on RTT. Timeout is always set to greater than or equal to RTT.
Statement(III): The size of the advertised window never changes during the course of the TCP connection.(False) Receiver’s window buffer is never changed.But depending upon the available window size, Advertised window is keep changing. Let’s undestand it with example, Suppose receiver window size is 1000B, so the size of advertised window is 1000B. Again suppose sender have 400B of data to sent, it sends to receiver. Now receiver window have (1000-400) 600B of available space. Now receiver will sent acknowlege to sender with advertised window of 600B. So, The size of the advertised window keep change during the course of the TCP connection.
Statement(IV): The number of unacknowledged bytes at the sender is always less than or equal to the advertised window.(True) Because sender will never sends number of Byte greater than the advertised window.
Q14➡| Computer Network Suppose that everyone in a group on N people wants to communicate secretly with the (N – 1) others using symmetric Key cryptographic system. The communication between any two person should not be decodable by the others in the group. The numbers of keys required in the system as a whole to satisfy the confidentiality requirement is
Q15➡| Web Technologies Which of the following statement is/are FALSE?
I. XML overcomes the limitations in HTML to support a structured way of organizing content. II. XML specification is not case sensitive while HTML specification is case sensitive. III. XML supports user defined tags while HTML uses pre-defined tags. IV. XML tags need not be closed while HTML tags must be closed.
Q17➡| Computer Network In one of the pairs of protocols given below , both the protocols can use multiple TCP connections between the same client and the server. Which one is that?
Q18➡| Theory of Computation For any two languages L1 and L2 such that L1 is context-free and L2 is recursively enumerable but not recursive, which of the following is/are necessarily true?
I. L’1 (Complement of L1) is recursive. II. L’2 (Complement of L2) is recursive. III. L’1 is context Free IV. L’1 U L2 is recursive Enumerable.
Q19➡| Operating System Consider a system with byte-addressable memory, 32-bit logical addresses, 4 kilobyte page size and page table entries of 4 bytes each. The size of the page table in the system in megabytes is___________.
Q20➡| Operating System The following two functions P1 and P2 that share a variable B with an initial value of 2 execute concurrently. The number of distinct values that B can possibly take after the execution is
Q22➡| Database Management System A file is organized so that the ordering of the data records is the same as or close to the ordering of data entries in some index. Than that index is called
Q23➡| Engineering Mathematics In the LU decomposition of the matrix ,if the diagonal elements of U are both 1, then the lower diagonal entry l22 of L is
Q26➡| Computer Network Suppose that the stop-and-wait protocol is used on a link with a bit rate of 64 kilobits per second and 20 milliseconds propagation delay. Assume that the transmission time for the acknowledgment and the processing time at nodes are negligible. Then the minimum frame size in bytes to achieve a link utilization of at least 50% is _________.
Show Answer With Best Explanation
Answer: 320 Explanation: Given, Bit rate (or Bandwidth) = 64 kilobits =64 x 103 bps Processing Delay (or Tp) = 20ms Link utilization (or Efficiency) = 50% = 1/2
Ask, Frame size = ?
Formula, For stop-wait protocol, Efficiency (η) = where, Tp = Propogation Delay Tt = Transmission Delay = Calculation, η = => => 1+2a = 2 => Tt =2*Tp => => L = 2 * Tp * Bw => L = 2* 20 ms * 64 x 103 bps => L = 2* 20* 10-3 s * 64 x 103 bps => L = 40 * 64 / 8 Byte = 320 Byte
Q27➡|Data Structure Consider a max heap, represented by the array: 40, 30, 20, 10, 15, 16, 17, 8, 4. Now consider that a value 35 is inserted into this heap. After insertion, the new heap is
Q29➡| Computer Network Consider a LAN with four nodes S1, S2, S3 and S4. Time is divided into fixed-size slots, and a node can begin its transmission only at the beginning of a slot. A collision is said to have occurred if more than one node transmit in the same slot. The probabilities of generation of a frame in a time slot by S1, S2, S3 and S4 are 0.1, 0.2, 0.3 and 0.4, respectively. The probability of sending a frame in the first slot without any collision by any of these four stations is _________.
Q30➡|Digital Logic Design The binary operator ≠ is defined by the following truth table Which one of the following is true about the binary operator ≠?
Q32➡| Engineering Mathematics Suppose L = {p, q, r, s, t} is a lattice represented by the following Hasse diagram: For any x, y ∈ L, not necessarily distinct, x ∨ y and x ∧ y are join and meet of x, y respectively. Let L3 = {(x,y,z): x, y, z ∈ L} be the set of all ordered triplets of the elements of L. Let pr be the probability that an element (x,y,z) ∈ L3 chosen equiprobably satisfies x ∨ (y ∧ z) = (x ∨ y) ∧ (x ∨ z). Then
Q33➡| Engineering Mathematics Consider the operations f(X, Y, Z) = X’YZ + XY’ + Y’Z’ and g(X′, Y, Z) = X′YZ + X′YZ′ + XY Which one of the following is correct?
Q34➡| Engineering Mathematics Let G be a connected planar graph with 10 vertices. If the number of edges on each face is three, then the number of edges in G is __________.
Q35➡| Engineering Mathematics Let an represent the number of bit strings of length n containing two consecutive 1s. What is the recurrence relation for an?
Q36➡| Compiler Design A variable x is said to be live at a statement Si in a program if the following three conditions hold simultaneously: i. There exists a statement Sj that uses x ii. There is a path from Si to Sj in the flow graph corresponding to the program iii. The path has no intervening assignment to x including at Si and Sj
The variables which are live both at the statement in basic block 2 and at the statement in basic block 3 of the above control flow graph are
Q37➡|Compiler Design The least number of temporary variables required to create a three-address code in static single assignment form for the expression q + r/3 + s – t * 5 + u * v/w is ________.
Q38➡|Database Management System Consider an Entity-Relationship (ER) model in which entity sets E1 and E2 are connected by an m:n relationship R12, E1 and E3 are connected by a 1:n (1 on the side of E1 and n on the side of E3) relationship R13. E1 has two single-valued attributes a11 and a12 of which a11 is the key attribute. E2 has two single-valued attributes a21 and a22 is the key attribute. E3 has two single-valued attributes a31 and a32 of which a31 is the key attribute. The relationships do not have any attributes.
If a relational model is derived from the above ER model, then the minimum number of relations that would be generated if all the relations are in 3NF is __________.
Q40➡| Theory of Computation Consider the NPDA 〈Q = {q0, q1, q2}, Σ = {0, 1}, Γ = {0, 1, ⊥}, δ, q0, ⊥, F = {q2}〉, where (as per usual convention) Q is the set of states, Σ is the input alphabet, Γ is stack alphabet, δ is the state transition function, q0 is the initial state, ⊥ is the initial stack symbol, and F is the set of accepting states, The state transition is as follows: Which one of the following sequences must follow the string 101100 so that the overall string is accepted by the automaton?
Q41➡|Engineering Mathematics Let G = (V, E) be a simple undirected graph, and s be a particular vertex in it called the source. For x ∈ V, let d(x)denote the shortest distance in G from s to x. A breadth first search (BFS) is performed starting at s. Let T be the resultant BFS tree. If (u, v) is an edge of G that is not in T, then which one of the following CANNOT be the value of d(u) – d(v) ?
Q42➡| Operating Systems Consider a uniprocessor system executing three tasks T1, T2 and T3, each of which is composed of an infinite sequence of jobs (or instances) which arrive periodically at intervals of 3, 7 and 20 milliseconds, respectively. The priority of each task is the inverse of its period and the available tasks are scheduled in order of priority, with the highest priority task scheduled first. Each instance of T1, T2 and T3 requires an execution time of 1, 2 and 4 milliseconds, respectively. Given that all tasks initially arrive at the beginning of the 1st millisecond and task preemptions are allowed, the first instance of T3 completes its execution at the end of ___________ milliseconds.
Q43➡| Digital Logic Design A positive edge-triggered D flip-flop is connected to a positive edge-triggered JK flipflop as follows. The Q output of the D flip-flop is connected to both the J and K inputs of the JK flip-flop, while the Q output of the JK flip-flop is connected to the input of the D flip-flop. Initially, the output of the D flip-flop is set to logic one and the output of the JK flip-flop is cleared. Which one of the following is the bit sequence (including the initial state) generated at the Q output of the JK flip-flop when the flip-flops are connected to a free-running common clock? Assume that J = K = 1 is the toggle mode and J = K = 0 is the state-holding mode of the JK flip-flop. Both the flip-flops have non-zero propagation delays.
Q44➡| Computer Organization Consider a disk pack with a seek time of 4 milliseconds and rotational speed of 10000 rotations per minute (RPM). It has 600 sectors per track and each sector can store 512 bytes of data. Consider a file stored in the disk. The file contains 2000 sectors. Assume that every sector access necessitates a seek, and the average rotational latency for accessing each sector is half of the time for one complete rotation. The total time (in milliseconds) needed to read the entire file is _________.
Q45➡|Computer Organization Consider a non-pipelined processor with a clock rate of 2.5 gigahertz and average cycles per instruction of four. The same processor is upgraded to a pipelined processor with five stages; but due to the internal pipeline delay, the clock speed is reduced to 2 gigahertz. Assume that there are no stalls in the pipeline. The speed up achieved in this pipelined processor is _______.
Q46➡| Operating Systems Suppose the following disk request sequence (track numbers) for a disk with 100 tracks is given: 45, 20, 90, 10, 50, 60, 80, 25, 70. Assume that the initial position of the R/W head is on track 50. The additional distance that will be traversed by the R/W head when the Shortest Seek Time First (SSTF) algorithm is used compared to the SCAN (Elevator) algorithm (assuming that SCAN algorithm moves towards 100 when it starts execution) is _________ tracks.
Q47➡|Operating Systems Consider a main memory with five page frames and the following sequence of page references: 3, 8, 2, 3, 9, 1, 6, 3, 8, 9, 3, 6, 2, 1, 3. Which one of the following is true with respect to page replacement policies First-In-First Out (FIFO) and Least Recently Used (LRU)?
Q49➡|Engineering Mathematics Consider the following 2 × 2 matrix A where two elements are unknown and are marked by a and b. The eigenvalues of this matrix are –1 and 7. What are the values of a and b?
Q50➡| Algorithms An algorithm performs (log N)1/2 find operations, N insert operations, (log N)1/2 delete operations, and (log N)1/2 decrease-key operations on a set of data items with keys drawn from a linearly ordered set. For a delete operation, a pointer is provided to the record that must be deleted. For the decrease-key operation, a pointer is provided to the record that has its key decreased. Which one of the following data structures is the most suited for the algorithm to use, if the goal is to achieve the best total asymptotic complexity considering all the operations?
Q51➡| Database Management System Consider the following relations: Consider the following SQL query. SELECT S. Student_Name, sum(P.Marks) FROM Student S, Performance P WHERE S.Roll_No = P.Roll_No GROUP BY S.Student_Name The number of rows that will be returned by the SQL query is ______.
Q52➡| Programming What is the output of the following C code? Assume that the address of x is 2000 (in decimal) and an integer requires four bytes of memory. int main() { unsigned int x[4][3] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}, {10, 11, 12}}; printf(“%u, %u, %u”, x+3, *(x+3), *(x+2)+3); }
Q53➡|Algorithms The graph shown below 8 edges with distinct integer edge weights. The minimum spanning tree (MST) is of weight 36 and contains the edges: {(A, C), (B, C), (B, E), (E, F), (D, F)}. The edge weights of only those edges which are in the MST are given in the figure shown below. The minimum possible sum of weights of all 8 edges of this graph is _______.
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,if the diagonal elements of U are both 1, then the lower diagonal entry l22 of L is
