Programming in C/C++ Previous Year Questions

Explanation

Parameter of a while statement in a languages takes two values true in the form of non-zero and false in the form of zero. Here 87 is a non-zero value and hence the while block gets true for infinite times.

Explanation

In programming language we use unique keywords to store data, just like that, the control string is use to access the different type of keyword, and control strings are the characters that use with the % (percent) and it is a classification of format specifier, white space and non-white space characters.

Explanation

x++ is a post-increment, so the old value 128 is used in the expression and printf prints 1 + 128 = 129; x becomes 129 only afterwards.

Explanation

S occupies addresses 1000 to 1008: A B C D E F G H \0. S[3] is 'D', and *(&S[3]) is 'D' itself, so %c prints D. S + 4 skips 4 characters, so %s prints "EFGH". %u prints the base address of S, 1000. Final output: DEFGH1000.

Explanation

Inaccessible in the derived class, only public or protected members are inherited So answer is (a)

Explanation

Data members in C++ is inherited in a derived class from base class. Constructor is a member function of a class which initialize objects of a class. In C++, constructor is automatically called when object create. It is special member function of the class. Destructor is a member function which destructs or deletes an object. Virtual methods is a method which is redefined (over- ridden) in derived class.

Explanation

The first three statements are correct; the fourth is incorrect. Templates are more powerful and obey C++ syntactic rules, whereas macros do not, but templates take more compilation time and code size, so templates are not more efficient than macros.

Explanation

Initially term = 1, sum = 0. Iteration 1 (i = 1): term = 1 * x/1 = x; sum = x Iteration 2 (i = 2): term = x * x/2 = x²/2; sum = x + x²/2 Iteration 3 (i = 3): term = (x²/2) * x/3 = x³/6; sum = x + x²/2 + x³/6 Iteration 4 (i = 4): term = (x³/6) * x/4 = x⁴/24; sum = x + x²/2 + x³/6 + x⁴/24 This is x/1! + x²/2! + x³/3! + x⁴/4! + ....

Explanation

Given i = 0, j = 1, k = –1, x = 0.5, y = 0.0. x * y < i + j || k = (((x * y) < (i + j)) || k) = (((0.5 * 0.0) < (0 + 1)) || –1) = ((0 < 1) || –1) = 1

Explanation

Basically polymorphism means having many forms. In C++, polymorphism requires Inheritance, Virtual functions and references, because polymorphism occurs when there is a hierarchy of classes and they are related by inheritance which include virtual functions and references.

Explanation

C++ provides two kinds of templates: class templates and function templates. A function template in C++ provides two levels of generalization.

Explanation

extern declares variables/functions with external linkage, giving them global visibility across files. It is the default storage class of all global variables and functions.

Explanation

Structure reference refers to the dot operator (.), which is one of the operators that cannot be overloaded in C++. The other options (>>=, unary & and unary *) can be overloaded for custom types in C++.

Explanation

When you call an overloaded function, the compiler determines the most appropriate definition to use by comparing the arguments types you used to call the function with the parameter types specified in the definitions. The process of selecting the most appropriate overloaded function is called overload resolution.

Explanation

(A) is true by De Morgan's law: A ∩ B = (A' ∪ B')'. (B) is false: recursively enumerable languages are closed under union and intersection but not under complementation.

Explanation

A virtual function cannot be static, because a virtual function is a non-static member function whose call is resolved through a specific object at run time.

Explanation

Function templates are instantiated implicitly when the function is called with arguments, whereas class templates are instantiated by defining an object with explicit template arguments. So class templates and function templates are not instantiated in the same way; statement (a) is not correct.

Explanation

A member function can always access all the data (public, private and protected) of the class of which it is a member.

Explanation

Context-free languages are closed under union, concatenation and Kleene star, but not under complementation (or intersection).