ISRO CSE 2014 PYQ

In UML, aggregation is represented by a hollow (open) diamond at the aggregate or “whole” end of the association line. The diamond distinguishes aggregation from composition, which uses a filled diamond. The image is referenced by the source, but the text and options are sufficient to identify the conventional UML symbol.

Track the number of 0s modulo 2 and the number of 1s modulo 5. The product construction has 2 $\times 5 = 10 possible remainder pairs (r0, r_{1})$. Every pair is reachable, and each pair is distinguishable by a suitable suffix, so the minimal DFA has 10 states. The accepting state is the pair (0,0).

In C++, a reference must be initialized to refer to an object or function and cannot be reseated to refer to another object. It is used without an explicit dereference operator, unlike a pointer. A reference is not simply synonymous with a pointer. In ordinary C++ reference semantics, a valid reference is not a nullable object reference, so the intended statement is that it cannot be NULL.

The head starts at track 100 and moves upward. The requests above 100 are serviced in ascending order: 126, 167, 199. C-SCAN then returns to the low end of the disk without servicing requests on the return sweep, and services 12, 36, 42, 51, 69, 76 in ascending order. This circular one-direction sweep identifies C-SCAN. (The stated 200-track range should clarify whether the last track is numbered 199 or 200; that does not change the policy identification.)

• Gate 1: \(\overline{CD}\)
• Gate 2: \(B \cdot \overline{CD}\)
• Gate 3: \(\overline{AB}\)
• Output NAND: \(Q = B \cdot \overline{CD} + AB = AB + B(\bar{C} + \bar{D}) = AB + B\bar{C} + B\bar{D}\)
Answer: \(AB + B\bar{C} + B\bar{D}\)