GATE-CS-2014-(Set-3)

Question 21

You have an array of n elements. Suppose you implement quick sort by always choosing the central element of the array as the pivot. Then the tightest upper bound for the worst case performance is

• O(n²)

• O(n*log(n))

• Theta(n*log(n))

• O(n³)

Question 22

The length of the shortest string NOT in the language (over Σ = {a, b}) of the following regular expression is ______________.

a*b*(ba)*a*

• 2
• 3
• 4
• 5

Question 23

• A
• B
• C
• D

Question 24

One of the purposes of using intermediate code in compilers is to

• make parsing and semantic analysis simpler.
• improve error recovery and error reporting.
• increase the chances of reusing the machine-independent code optimizer in other compilers.
• improve the register allocation.

Question 25

Which of the following statements are CORRECT?

1) Static allocation of all data areas by a compiler
   makes it impossible to implement recursion.
2) Automatic garbage collection is essential 
   to implement recursion.
3) Dynamic allocation of activation records is 
   essential to implement recursion.
4) Both heap and stack are essential to implement
   recursion.

• 1 and 2 only
• 2 and 3 only
• 3 and 4 only
• 1 and 3 only

Question 26

In the context of modular software design, which one of the following combinations is desirable?

• High cohesion and high coupling
• High cohesion and low coupling
• Low cohesion and high coupling
• Low cohesion and low coupling

Question 27

A system uses 3 page frames for storing process pages in main memory. It uses the Least Recently Used (LRU) page replacement policy. Assume that all the page frames are initially empty. What is the total number of page faults that will occur while processing the page reference string given below? 4, 7, 6, 1, 7, 6, 1, 2, 7, 2

• 4
• 5
• 6
• 7

Question 28

• A
• B
• C
• D

Question 29

A prime attribute of a relation scheme R is an attribute that appears

• in all candidate keys of R.
• in some candidate key of R.
• in a foreign key of R.
• only in the primary key of R.

Question 30

In the following pairs of OSI protocol layer/sub-layer and its functionality, the INCORRECT pair is

• Network layer and Routing

• Data Link Layer and Bit synchronization

• Transport layer and End-to-end process communication

• Medium Access Control sub-layer and Channel sharing