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The arguments passed to the functions while the function is called is known as the actual arguments, whereas the arguments declared in the function header is called as formal arguments.

Ex. Suppose sum() is a function.

int sum(int x, int y) /*Here x and y are called formal arguments*/ {...}

void main() { 

int ans; 

.... 

ans = sum(3,5); /*Here the arguments 3 and 5 are called actual arguments*/

...

 getch();

}

OOP provides the following advantages to overcome the shortcomings of traditional programming approaches: 

OOPs is closer to real world model.

Hierarchical relationship among objects can be well-represented through inheritance.

Data can be made hidden or public as per the need. Only the necessary data is exposed enhancing the data security.

Increased modularity adds ease to program development.

Private data is accessible only through designed interface in a way suited to the program. 

Correct option: (a) will compile

Reason: ;;; does not matter. This indicates only an empty statement. The o/p will be 3,1

Correct option: b) nice job

Reason: unsolved

Correct option: a) error

reason: you cannot declare structure as unsized array. 

Correct option: b) 3

Reason: The return st.. returns x value first as it is and then decrements its value. Its post decrement.

The first statement treats 75 as ascii value and converts it into its relative character ‘K’ whereas second statement treats 75 as number.

VALID  Statement

Values assigned to the variables ua, ub, uc and fail after the execution are as following:

ua = 2

ub = 4

uc = 5

fail = 6

Following are the arithmetic operators in C++:

addition(+), subtraction(-), multiplication(*), division(/) and reminder(%).

Example:

#include <iostream.h>

float NUM=900; 

//NUM is a global variable

void LOCAL(int T)

{

int Total=0; //Total is a local variable

for (int I=0;I<T;I⁺⁺)

Total+=I; cout<<NUM+Total;

}

void main() {

LOCAL(45);

}

The data type double is treated as a distinct data type because it occupies twice as much memory as type float, and stores floating-point numbers with much larger range and precision. It stands for double precision floating-point. It is used when type float is too small or insufficiently precise.

The access modifier const can be added to the declaration of an object to make that object a constant rather than a variable. Thus, the value of the named constant cannot be altered during the program run whereas the value of the variable can be changed during the program run.

Example:

void main ()  {

const int a =10;

int b = 20;

a++;

cout<<"a="<<a;

b++;

cout<<"b="<<b;

}

Yes it is possible to create mobile apps using Python.

Kivy is a powerful library based on Python for the development of mobile apps including the natural user interface (NUI).

(iv) 29: 26: 25: 26: is correct

Justification: 

The only option that satisfied the values as per the code is option (iv) because when:

Output: 

30%41 

52%60 

40%25

Two-dimensional array:

A two-dimensional array is an array in which each element is itself an array. For instance, an array A[m][n] is an M by N table with M rows and N columns containing M x N elements. Two-dimensional arrays are used to represent tables, matrices, etc.

For example, below marks table can be represented easily by 2D array :

Default arguments:

C⁺⁺ allows us to assign default values to a function’s parameters which are useful in case a matching argument is not passed in the function call statement. The default values are specified at the time of function declaration.

Example: float interest(float principal, int time, float rate=0.10); 

Constant argument: By constant argument, it is meant that the function cannot modify these arguments. In order to make an argument constant to a function, we can use the keyword const as shown : int sum (const int a, const int b); The qualifier const in function prototype tells the compiler that the function should not modify the argument. The constant arguments are useful when functions are called by reference.

Inheritance is the capability of one class to inherit properties from another class. For instance, Student is a class wherefrom class GraduateStudent inherits as given below:

class Student

{

protected:

char name[25];

int rollno;

public:

void readStudent();

void showStudent();

};

class GraduateStudent:protected Student

{

protected:

char subjects[50];

public:

void readAradStud();

void showGradStud();

};

In C⁺⁺ an Abstract Class is the one, which defines an interface, but does not necessarily provide implementation for all its member functions. An abstract class is meant to be used as the base class from which other classes are derived. The derived class is expected to provide implementations for the member functions that are not implemented in the base class. A derived class that implements all the missing functionality is called a Concrete Class. A concrete class derives from its abstract class.

Output:

NEW TEXT:[email protected]@e

Output

38010

77010

• Inheritance ensures the closeness with the real-world models.
• Allows the code to be reused as many times as needed. The base class once defined and once it is compiled, it need not be reworked. 
• We can extend the already made classes by adding some new features.
• Inheritance is capable of simulating the transitive nature of real-world’s inheritace, which in turn saves on modification time and efforts, if required.

Following are the general OOP concepts:

1. Data Abstraction: Data abstraction means, providing only essential information to the outside word and hiding their background details i.e. to represent the needed information in program without presenting the details.

2. Data Encapsulation: The wrapping up of data and operations/functions (that operate o the data) into a single unit (called class) is known as Encapsulation.

3. Modularity: Modularity is the property of a system that has been decomposed into a set of cohesive and loosely coupled modules.

4. Inheritance: Inheritance is the capability of one class of things to inherit capabilities or properties from another class.

5. Polymorphism: Polymorphism is the ability for a message or data to be processed in more than one form. 

C⁺⁺ offered three types of integers : short, int and long. Each comes in both signed and unsigned versions. 

(i) cout<<"="a;

(ii)  m = 5, n = 12; o = 15

(iii)  cout<<"x";<<x;

(iv) cin>>y;>>j;

(v)  cin>>"\n">>y;

(vi)  cout>>"\n "abc";

(vii)  a = b + c

(viii)  break = x*y;

A class is a blueprint for object. A class is implementing with the help of an object. Suppose a class has a member function named display(). Now, to implement that member function display we have to use object of that class.

The objects is implemented in software terms as follows: 

(i) characteristics / attributes are implemented through member variables or data items of the object.

(ii) behavior is implemented through member functions called methods.

(iii) It is given a unique name to give it identify

Output:

50240

290340240

340240

(i) Output:  E

(ii) Output:  first=8second=2

(iii) Output:  Value is: Pass

New value is: Best of Luck

Output:

11,19,6

25,15,35

35,5,45

Abstraction is the act of representing essential features without including the background details. Encapsulation is the way of combining both data and the functions that operate on the data under a single unit. Encapsulation is the way of implementing abstraction. Thus, it is true that while implementing encapsulation, abstraction is also implemented.

Unsized array initialization means skip the size of the array I an initialization statement. The C++, then automatically creates an array big enough to hold all the initializers present and calculates the dimensions of unsized arrays.

Example: char S1 [ ] = “First String”;

Advantages:

• Less tedious.
• Allow to change any of the values without fear of using incorrect array dimensions.
• We may lengthen or shorten the value-list without changing the array dimensions.

The general form of array initialization is as shown below:

type array-name[size N] = {value-list};

If an array is initialized at the time of declaration, following thing one must bear in mind:

• The element values in the value-list must have the same data type as that of type, the base type of the array.
• In character array, you must make sure that the array you declare is long enough to include the null. 

Output:

HUqT10u

C⁺⁺ implements polymorphism through virtual functions, overloaded functions and overloaded operators. The term ‘overloaded function’ refers to a function having one name and more than one distinct meaning.

For example,

float area(float a)

{

return a*a;

}

float area(float a,float b)

{

return a*b;

}

Array: An array is a collection of variables of the same type that are referenced by a common name.

Need for array: Arrays are very much useful in a case where many variables of the same (data) types need to be stored and processed. For example, suppose we have to write a program in which can accept salary of 50 employees. If we solve this problem by making use of variables, we need 50 variables to store employee’s salary. Remembering and managing these 50 variables is not an easy task and it will make the program a complex and lengthy program. This problem can be solved by declaring 1 array having 50 elements; one for employee’s salary. Now we only have to remember the name of that 1 array.

Output: 

Output1=25&35

Output2=-30&21

Output1=26&35

Output2=-30&22

Output: 

Oppe$0GIC

Programming Paradigm: 

A Programming Paradigm defines the methodology of designing and implementing programs using the key features and building blocks of a programming language.

Following are the different programming paradigms:

(i) Procedural Programming: Procedural programming paradigm lays more emphasis on procedure or the algorithm. Data is considered secondary. Data is loosely available to many functions. This paradigm is: Decide which procedure we want; use the best algorithm we can find.

(ii) Object Based Programming: In object based programming, data and its associated meaningful functions are enclosed in one single entity a class. Classes enforce information hiding and abstraction thereby separating the implementation details and the user interface. It also supports user-defined types.

(iii) Object Oriented Programming: Object oriented programming offers all the features of object based programming and overcomes its limitation by implementing inheritance. The object oriented approach views a problem in terms of objects involved rather than procedure for doing it. We can define the object oriented programming (OOP) paradigm as following: Decide which classes and objects are needed; provide a full set of operations for each class. 

The difference between cin>>ch and cin.get(ch) is that when >> operator is used, the white spaces (e.g., tabs), spaces etc. and new-line characters are ignored whereas it is not so with cin.get(ch). 

Output: 

Oppe$0GIC

(i)  103#102#101#100#  

iostream.h is most important header file for basic input and output operations. iostream.h contain built-in functions cout and cin for input-output. So, every C⁺⁺ program should include iostream.h header file for performing input and output operations.

#include<iostream.h>

#include<conio.h>

void main() {

clrscr();

int tanks=0;

float tot_km; float avg_k_p_g;

cout<<"Enter how many tanks filled :";

cin>>tanks;

float *kms=new float[tanks];

float *gallons_used=new float[tanks];

float *k_p_g=new float[tanks];

for(int i=0;i<tanks;i++)

{

cout<<"Enter how much kilometers covered for tank "<<i+1<<" ";

cin>>kms[i];

cout<<"Enter how much gallon used from tank "<<i+1<<" ";

cin>>gallons_used[i];

k_p_g[i]=kms[i]/gallons_used[i];

cout<<"KMs per Gallon obtained for tank No. "<<i+1<<" "<<k_p_g[i]<<endl;

tot_km+=k_p_g[i];

cout<<endl;

}

avg_k_p_g=tot_km/tanks;

cout<<"Average kilometers per gallon obtained for all tanks is "<<avg_k_p_g;

getch();

}

No, it is not necessary to include header file in a C⁺⁺ program at all. A header file is included if only the program intends to use the functions or macros etc. defined in that particular header file.

#include<iostream.h>

#include<conio.h>

void main()

{

int a,b,dif;

clrscr(); 

cout<<"Enter a:";

cin>>a;

cout<<end1<<"Enter b: ";

cin>>b;

if(a>b)

{

dif = a-b;

cout<<a<<" is larger by " <<diff<<"units than smaller number"<<end1;

}

else if(b>a)

{

dif = b-a;

cout<<b<<"is larger by"<<dif<<"units than smaller number"<<end1;

}

else

cout<<"These numbers are equal"<<end1;

getch();

The output of the first code fragment is 12.

The output of the first code fragment is 24.

Correct code:

cin>>i>>j;

while(i<j)

{

cout<<i * j;

i⁺⁺;

}

Reasons of errors:

(i) There is a use of ‘<,’ in cout statement instead of ‘<<’ which is not valid.

(ii) while statement should be in curly braces otherwise it will not work properly.