Question

Question 6

1. Explain macro and inline functions. Write a macro and an inline function to calculate the minimum of two input arguments

2. Why should we use a pass-by-reference for a copy constructor ?   What cannot be inherited from a base class ?

3. What is the main difference between protected and private? What is the role of inheritance type ?

4. Give a definition of software engineering. Explain how assert( ) could enforce the correctness of your code.

5. Assume that you have a two-dimensional array: float x[30][40]. The values of this array elements have been assigned. Write a segment of code to find the minimum and maximum of those array elements

Answer 1

Codes are in Languages C++ and Java

A.1)

(Language: C++)

Macro:

It is also called preprocessors directive. The macros are defined by the '#define' keyword. Before the program compilation,

the preprocessor examines the program whenever the preprocessor detects the macros then preprocessor replaces the macro by the macro definition.

Syntax:

#define MACRO_NAME _DEFINATION

Inline:

It is a normal function that is defined by the inline keyword.

An inline function is a short function that is expanded by the compiler.its arguments are evaluated only once.

Syntax:

inline return_type _name ( parameters )

{

// CODE

}

For calculating the minimum of two input arguments

a) Using Inline:

#include <bits/stdc++.h>

using namespace std;

// Inline function

inline int Minimum(int a, int b)

{

    return (a < b) ? a : b;

}

int main()

{

    int a,b;

    cin>>a>>b; // Taking two inputs

    cout<<"Minimum of "<<a<<" and "<<b<<":"<<Minimum(a,b)<<endl;

    return 0;

}

b) Using Macro:

#include <bits/stdc++.h>

using namespace std;

// macro with parameter

#define MINIMUM(a, b) (a < b) ? a : b

int main()

{

    int a,b;

    cin>>a>>b; //Taking two inputs

    int res = MINIMUM(a,b);

    cout<<"Minimum of "<<a<<" and "<<b<<":"<<res<<endl;

    return 0;

}

A.2)

a) It is necessary to pass object as reference and not by value because if you pass it by value its copy is made using the copy constructor.This means the copy constructor would call itself to form copy.

This process will continue until the compiler runs out of memory.

b) Base class's constructors, destructor, friends can't be inherited.

A.3)

a)

Private: Only members of an equivalent class can access the function.

Protected : Same as private but derived classes also can access.

b) Role of inheritance: for reuseability of the code.

Moreover we can have common functionalities in the base class &

can extends the class by adding more new functionaity or can override the existing functionality.

A.4)

a) Software Engineering: Software engineering is the systematic application of

engineering approaches to the development of software.

b) Assert:

Like 'Assertion' allows testing the correctness of any assumptions that have been made in the program.

Assertion can be done using the assert statement(in java/C++). When any assertion fails,JVM throws an error, "AssertionError".It is especially used for testing purposes during development.

In java assertions are not enabled, bydefault.

(Language: Java)

Syntax:

assert _expression

import java.util.Scanner;

class Test

{

    public static void main(String args[])

    {

        int val=10;

        assert val >= 20 : " Hey";

        System.out.println("value is "+val);

    }

}

Output: value is 10

Assert will not be seen directly so while compiling, you have to write:

'java –ea Test' (For enable the assertion)

Then output will look like:

Exception in thread "main" java.lang.AssertionError: Hey

A.5)

(Language: C++)

float x[30][40] is an array and values are already assigned, so let's make two variables final_min and final_max, final_min defined as INT_MAX, final_max defined as INT_MIN and traverse the array to find minimum and maximum values.

Code:

#include<bits/stdc++.h>

using namespace std;

int main()

{

    float x[30][40];

    //according to question, values are already assigned

    float final_min,final_max;

    final_min=INT_MAX;

    final_max=INT_MIN;

    for(int i=0;i<30;i++)

    {

        for(int j=0;j<40;j++)

        {

            final_min=min(final_min,x[i][j]);

            final_max=max(final_max,x[i][j]);

        }

    }

    cout<<"Maximum element is:"<<final_max<<" "<<"\n"<<"Minimum element is:"<<final_min<<endl;

    return 0;

}

Happy Coding:)