PREVIOUS YEAR SOLVED PAPERS - December 2015 Paper 3
- Option : C
- Explanation : S → XYX X → aX|bX|λ i.e. (a + b)* Y → bbb S → (a + b)*(bbb)(a + b)* So, option (C) is correct.
- Option : A
- Explanation : Language L1 is context free language as L1 = {anban|n > 0}, we can compare number of a’s before b and number of a’s after b both are equal using only one stack using push and pop function but we can not compare language L2. L2 = {an b an bn + 1|n > 0} using only one stack here we can compare all number of a’s before b and number of a’s after b both are equal using only one stack using push and pop function but we cannot compare all bn + 1 at that time. Hence, L1 is context free language and L2 is not context free language.
29. Which of the following is used to make an Abstract class?
- Option : A
- Explanation : Making atleast one member function as pure virtual function is the method to make abstract class. For more information on Abstract Class Refer:Pure Virtual Functions and Abstract Classes in C++ Option (A) is correct.
30. Match the following with reference to object-oriented modeling.
| List I | List II |
| (a) Polymorphism | (i) Picking both operator and attributes with operations appropriate to model an object |
| (b) Inheritance | (ii) Hiding implementation details of methods from users of objects |
| (c) Encapsulation | (iii) Using similar operations to do similar things |
| (d) Abstraction | (iv) Create new classes from the existing class |
Codes:
| (a) | (b) | (c) | (d) | |
| (1) | (iv) | (iii) | (i) | (ii) |
| (2) | (iii) | (iv) | (i) | (ii) |
| (3) | (iii) | (i) | (ii) | (iv) |
| (4) | (iv) | (iii) | (ii) | (i) |
- Option : B
- Explanation :
- Using similar operations to do similar things is Polymorphism
- Create new classes from existing class is Inheritence.
- Picking both operator and attributes with operations appropriate to model an object is encapsulation
- Hiding implementation details of methods from users of objects is Abstraction
So, option (B) is correct.
