C++ Exercise 3

Objective:

• Functions in C++

Activity 1:

Write C++ program that will ask the user to enter the width and length of a rectangle and then display the rectangle’s area. The program calls the following functions, which have not been written:

• getLength: This function should ask the user to enter the rectangle’s length and then return that value as a double .
• getWidth: This function should ask the user to enter the rectangle’s width and then return that value as a double .
• getArea: This function should accept the rectangle’s length and width as arguments and return the rectangle’s area. The area is calculated by multiplying the length by the width.
• displayData: This function should accept the rectangle’s length, width, and area as arguments and display them in an appropriate message on the screen.

Solution:

#include<iostream>
using namespace std;

double getLength()
{
	double length;

	cout << "Enter Length of Rectangle: " << endl;
	cin >> length;

	return length;
}

double getWidth()
{
	double width;

	cout << "Enter Width of Rectangle: " << endl;
	cin >> width;

	return width;
}

double getArea(double i, double j)
{
	double Area;
	Area = i * j;

	return Area;
}

void displayData(double A)
{
	cout << "Area of Rectangle is: " << A << endl;
}

int main()
{
	double x, y, area;

	x = getLength();
	y = getWidth();

	area = getArea(x, y);
	displayData(area);

	return 0;
}

Activity 2:

Write a function called displayShape that accepts size and shapetype as parameters and displays a square or a triangle of the required size.

So e.g. if the function is called with the following parameters:

displayShape(‘S’, 5); a square of size 5 is displayed as given

1	2	3	4	5
2	4	6	8	10
3	6	9	12	15
4	8	12	16	20
5	10	15	20	25

 

displayShape(‘T’, 6); a triangle of size 6 is displayed as given

                1

             1  1

           1  2  1

         1  3  3  1

       1  4  6  4  1

   1 5  10  10  5  1 

Solution:

#include<iostream>
using namespace std;

void print_square(int Size)
{
    int num, i, j, res;
    for (i = 1; i <= Size; i++)
    {
        num = i;
        for (j = 1; j <= Size; j++)
        {
            res = num * j;
            cout << res << "\t";
        }
        cout << endl;
    }
    cout << endl;
}

void print_triangle(int Size)
{
    int coef = 1;
    for (int i = 0; i < Size; i++)
    {
        for (int space = 1; space <= Size - i; space++)
        {
            cout << "  ";
        }
        for (int j = 0; j <= i; j++)
        {
            if (j == 0 || i == 0)
            {
                coef = 1;
            }
            else
            {
                coef = coef * (i - j + 1) / j;
            }
            cout << coef << "   ";
        }
        cout << endl;
    }
}

int main()
{
    char choice2 = 'y';

    do {
        int size;
        char choice;

        cout << "Enter Size of Shape: " << endl;
        cin >> size;
        cout << "Enter s for Square-shape or t for triangle-shape: " << endl;
        cin >> choice;

        if (choice == 's')
        {
            print_square(size);
        }
        if (choice == 't')
        {
            print_triangle(size);
        }

        cout << "If you want to Repeat then press y. " << endl;
        cin >> choice2;

    } while (choice2 == 'y');

    return 0;
}

Activity 3:

Write a program that converts a binary number into decimal number.

Solution:

#include<iostream>
#include<cmath>
using namespace std;

int decimalConverter(int num)
{
    int dec = 0, i = 0, rem;
    bool possible = true;
    while (num != 0)
    {
        rem = num % 10;
        num /= 10;
        if (rem == 0 || rem == 1)
        {
            dec += rem * pow(2, i);
            ++i;
        }
        else
        {
            cout << "Conversion not possible: it is not a binary number." << endl;
            bool possible = false;
            break;
        }
    }
    if (possible == true)
    {
        return dec;
    }
}

int main()
{
    int n;
    cout << "Enter a Binary Number: ";
    cin >> n;
    cout << "Decimal Number: " << decimalConverter(n) << endl;
    return 0;
}