C Program - Rectangle Calculator - Diagonal, Area, Parimeter

This program calculates the area, perimeter, and diagonal of a rectangle based on its width and height. 

#include <stdio.h>
#include <math.h>

int main()
{

    float width, height, area, parimeter, diagonal;

    printf("Rectangle Calculator:  \n\n");
    printf("--------width--------- \n");
    printf("|                    | \n");
    printf("|                    | height\n");
    printf("|                    | \n");
    printf("|                    | \n");
    printf("---------------------- \n");

    printf("Width: ");
    scanf("%f", &width);

    printf("Height: ");
    scanf("%f", &height);

    printf("--------------------- \n");

    area = width * height;
    parimeter = (2 * width) + (2 * height);
    diagonal = sqrt((width*width) + (height*height));

    printf("Area: %.2f \n", area);
    printf("Parimeter: %.2f \n", parimeter);
    printf("Diagonal: %.2f \n", diagonal);

    printf("--------------------- \n");

    return 0;
}

Result: 

Rectangle Calculator:

--------width---------
|                    |
|                    | height
|                    |
|                    |
----------------------
Width: 100
Height: 50
---------------------
Area: 5000.00
Parimeter: 300.00
Diagonal: 111.80
---------------------

Process returned 0 (0x0)   execution time : 4.192 s
Press any key to continue.

Here's a line-by-line explanation of the code: 

#include <stdio.h>
#include <math.h>

int main()
{

This code defines the standard library header files that will be used in the program, including stdio.h and math.h. It also defines the main function, which is the entry point of the program. 

    float width, height, area, parimeter, diagonal;

This code declares five float variables, namely width, height, area, perimeter, and diagonal. These variables will be used to store the input values for the width and height of the rectangle and the calculated values of its area, perimeter, and diagonal. 

    printf("Rectangle Calculator:  \n\n");
    printf("--------width--------- \n");
    printf("|                    | \n");
    printf("|                    | height\n");
    printf("|                    | \n");
    printf("|                    | \n");
    printf("---------------------- \n");

This code displays a prompt to the user asking for the width and height of the rectangle, and also shows a visual representation of the rectangle. 

    printf("Width: ");
    scanf("%f", &width);

    printf("Height: ");
    scanf("%f", &height);

    printf("--------------------- \n");

This code prompts the user to input the width and height of the rectangle, and then stores these values in the width and height variables. 

    area = width * height;
    perimeter = (2 * width) + (2 * height);
    diagonal = sqrt((width*width) + (height*height));

This code calculates the area, perimeter, and diagonal of the rectangle based on its width and height, and stores the results in the area, perimeter, and diagonal variables, respectively. 

    printf("Area: %.2f \n", area);
    printf("Perimeter: %.2f \n", perimeter);
    printf("Diagonal: %.2f \n", diagonal);

    printf("--------------------- \n");

    return 0;
}

This code displays the calculated values of the area, perimeter, and diagonal of the rectangle using the printf function. The %.2f format specifier is used to display the floating-point numbers with two decimal places. Finally, the function returns 0 to indicate successful execution of the program.