Q3.A subsequence of a given sequence is just the given sequence with some elements (possibly none or
all) left out. We are given two sequences X[m] and Y[n] of lengths m and n, respectively, with indexes of
X and Y starting from 0.
We wish to find the length of the longest common subsequence (LCS) of X[m] and Y[n] as l(m, n),
where an incomplete recursive definition for the function l(i, j) to compute the length of the LCS of
X[m] and Y[n] is given below:
l(i, j) = 0, if either i = 0 or j = 0
= expr1, if i, j>0 and x[i - 1] = Y[j - 1]
= expr2, if i, j>0 and x[i - 1] ≠ Y[j - 1]
Which one of the following option is correct?
Answer : Option CExplaination / Solution: No Explaination.
Q5.The lexical analysis for a modern computer language such as Java needs the
power of which one of the following machine models in a necessary and sufficient
sense?
Answer : Option AExplaination / Solution:
Lexical Analysis is implemented by finite automata
Q6.Consider a relational table with a single record for each registered student with the following attributes.
1. Registration_Number: Unique registration number for each registered student
2. UID: Unique Identity number, unique at the national level for each citizen
3. BankAccount_Number: Unique account number at the bank. A student can have multiple accounts or joint accounts. This attributes stores the primary account number
4. Name: Name of the Student
5. Hostel_Room: Room number of the hostel
Which of the following options is INCORRECT?
Answer : Option AExplaination / Solution:
In case two students hold joint account then BankAccount_Num will not uniquely
determine other attributes.
Q7.Consider an instruction pipeline with four stages (S1, S2, S3 and S4) each with
combinational circuit only. The pipeline registers are required between each stage
and at the end of the last stage. Delays for the stages and for the pipeline
registers are as given in the figure.
What is the approximate speed up of the pipeline in steady state under ideal
conditions when compared to the corresponding non-pipeline implementation?
Q9.The protocol data unit (PDU) for the application layer in the Internet stack is
Answer : Option CExplaination / Solution:
The PDU for Datalink layer, Network layer , Transport layer and Application layer are frame,
datagram, segment and message respectively.