GATE CS 2008

Question 11

Some code optimizations are carried out on the intermediate code because

• they enhance the portability of the compiler to other target processors
• program analysis is more accurate on intermediate code than on machine code
• the information from dataflow analysis cannot otherwise be used for optimization
• the information from the front end cannot otherwise be used for optimization

Question 12

If L and L\' are recursively enumerable, then L is

• regular
• context-free
• context-sensitive
• recursive

Question 13

Which of the following tuple relational calculus expression(s) is/are equivalent to  

• I only 

• II only 

• III only 

• III and IV only 

Question 14

Which of the following system calls results in the sending of SYN packets?

• socket
• bind
• listen
• connect

Question 15

The Breadth First Search algorithm has been implemented using the queue data structure. One possible order of visiting the nodes of the following graph is

• MNOPQR
• NQMPOR
• QMNPRO
• QMNPOR

Question 16

Which combination of the integer variables x, y and z makes the variable a get the value 4 in the following expression?

C

a = ( x > y ) ? (( x > z ) ? x : z) : (( y > z ) ? y : z )

• x = 3, y = 4, z = 2
• x = 6, y = 5, z = 3
• x = 6, y = 3, z = 5
• x = 5, y = 4, z = 5

Question 17

The most efficient algorithm for finding the number of connected components in an undirected graph on n vertices and m edges has time complexity

• &thetha;(n)
• &thetha;(m)
• &thetha;(m + n)
• &thetha;(mn)

Question 18

The data blocks of a very large file in the Unix file system are allocated using

• contiguous allocation
• linked allocation
• indexed allocation
• an extension of indexed allocation

Question 19

The minimum number of equal length subintervals needed to approximate 

[Tex]\int_{1}^{2}xe^xdx[/Tex]

 to an accuracy of at least 

[Tex] \frac{1}{3} * 10^{-6}[/Tex]

 using the trapezoidal rule is

• 100 l
  

• 100
  

• 1000
  

• 1000 l
  

Question 20

The Newton-Raphson iteration 

 can be used to compute the.

• square root of R 
  

• logarithm of R
  

• reciprocal of R
  

• square of R