GATE PYQ

ISRO CSE 2018

Q21.
CFG (Context Free Grammar) is not closed under:

Q22.
What is the output of tho following program? main(){ int x=2, y=5; if(x < y) return (x=x+y); else printf("z1"); printf("z2"); }

Q23.
Assume A and B are non-zero positive integers. The following code segment: while(A!=B){ if(A > B) A -= B; else B -= A; } cout << A; // printing the value of A

Q24.
StationA uses 32 byte packets to transmit messages to Station B using a sliding window protocol. The round trip delay between A and B is 80 ms and the bottleneck bandwidth on the path between A and B is 128 kbps. What is the optimal window size that A should use?

Q25.
________ can detect burst error of length less than or equal to degree of the polynomial and detects burst errors that affect odd number of bits.

Q26.
Consider a system having m resources of the same type. These resources are shared by 3 processes A,B,C, which have peak time demands of 3,4,6 respectively. The minimum value of m that ensures that deadlock will never occur is:

Q27.
Disk requests come to a disk driver for cylinders in the order 10, 22, 20, 2, 40, 6 and 38 at a time when the disk drive is reading from cylinder 20. The seek time is 6 ms/cylinder. The total seek time, if the disk arm scheduling algorithms is first-come-first-served is

Q28.
Any set of Boolean operation that is sufficient to represent all Boolean expression is said to be complete. Which of the following is not complete ?

Q29.
In the diagram above, the inverter (NOT gate) and the AND-gates labeled 1 and 2 have delays of 9, 10 and 12 nanoseconds (ns), respectively. Wire delays are negligible. For certain values a and c, together with certain transition of b, a glitch (spurious output) is generated for a short time, after which the output assumes its correct value. The duration of glitch is:

Q30.
In E-R model, Y is the dominant entity and X is subordinate entity