C Program To Calculate Surface Area of Cylinder

Given the values for radius and height of a Cylinder, write a C program to calculate Surface Area of the Cylinder.

Formula To Calculate Surface Area of Cylinder

Surface_Area = (2 * PI * radius * height) + (2 * PI * radius * radius);
where PI is approximately equal to 3.14

surface area of Cylinder

Logic of Surface Area of Cylinder Formula

A solid Cylinder has 2 circles. One at the top and one at the bottom. Area of a Circle is PI * radius². Since there are 2 Circles in the Cylinder, we multiply it by 2.

i.e., 2 (PI * radius²)

Next lets cut the cylinder at one end and open it. It forms a rectangle. Now height of the rectangle and height of the Cylinder are same. Width of the rectangle is equal to circumference of the circle, since top and bottom of the Cylinder are circles.

So, area of rectangle = (2 * PI * radius) * height

Therefore, Surface Area of Cylinder is:

SA = ( (2 * PI * radius) * height ) + ( 2 (PI * radius²) );

Expected Output for the Input

User Input:
Enter Radius and Height of the Cylinder
2
5

Output:
Surface Area of Cylinder is 87.920006

Video Tutorial: C Program To Calculate Surface Area of Cylinder

[youtube https://www.youtube.com/watch?v=9GGagAMiMSc]

YouTube Link: https://www.youtube.com/watch?v=9GGagAMiMSc [Watch the Video In Full Screen.]

Source Code: C Program To Calculate Surface Area of Cylinder

#include<stdio.h>

int main()
{
    const float PI = 3.14;
          float r, h, Area;

    printf("Enter Radius and Height of the Cylinder\n");
    scanf("%f%f", &r, &h);

    Area = (2 * PI * r * h) + (2 * PI * r * r);

    printf("Surface Area of Cylinder is %f\n", Area);

    return 0;
}

Output 1:
Enter Radius and Height of the Cylinder
5
10
Surface Area of Cylinder is 471.000031

Output 2:
Enter Radius and Height of the Cylinder
2
13
Surface Area of Cylinder is 188.400009

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

C Program To Find Whether Area of Rectangle Is Greater Than Its Perimeter

Given the length and breadth(or width) of a rectangle, write a C program to find whether the area of the rectangle is greater than its perimeter. For example, the area of the rectangle with length = 5 and breadth = 4 is greater than its perimeter.

Note:
Rectangle is a quadrilateral(i.e., it has 4 sides). And all the 4 angles of the rectangle are of 90 degree. To calculate area of a rectangle we need its length and width/breadth.

Formula To Calculate Area of a Rectangle

Area = Length * Width;
area of rectangle

Formula To Calculate Perimeter of a Rectangle

Perimeter = 2 * (Length + Width);
perimeter of rectangle

Length: is the length of the longest side of the rectangle.
width: is the length of the smallest side of the rectangle.

Expected Output for the Input

User Input:
Enter length of the Rectangle
5
Enter width of the Rectangle
4

Output:
yes, area(20.00) is greater than its perimeter(18.00)

Video Tutorial: C Program To Find Whether Area of Rectangle Is Greater Than Its Perimeter

[youtube https://www.youtube.com/watch?v=TmnErbGucfk]

YouTube Link: https://www.youtube.com/watch?v=TmnErbGucfk [Watch the Video In Full Screen.]

Source Code: C Program To Find Whether Area of Rectangle Is Greater Than Its Perimeter

#include < stdio.h >

int main()
{
    float length, width, area, perimeter;

    printf("Enter length of the Rectangle\n");
    scanf("%f", &length);

    printf("Enter width of the Rectangle\n");
    scanf("%f", &width);

    area      =     (length * width);
    perimeter = 2 * (length + width);

    if(area > perimeter)
    {
        printf("yes, area(%0.2f) is greater than its perimeter(%0.2f)\n", 
               area, perimeter);
    }
    else
    {
        printf("Area(%0.2f) is not greater than its perimeter(%0.2f)\n", 
               area, perimeter);
    }

    return 0;
}

Output:
Enter length of the Rectangle
12
Enter width of the Rectangle
6
yes, area(72.00) is greater than its perimeter(36.00)

Logic To Find Whether Area of Rectangle Is Greater Than Its Perimeter

We ask the user to enter length and breadth/width of the rectangle and store it inside address of variable length and width. Next we calculate area and perimeter of the rectangle using the user entered value for length and width of the rectangle.

Area = Length * Width;
Perimeter = 2 * (Length + Width);

Next we check if the value present in variable area is greater than the value of perimeter or not, and output the result accordingly to the console window.

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Perimeter of Rectangle: C Program

The length and breadth / width of a rectangle are entered through the keyboard. Write a program to calculate the perimeter of the rectangle.

To get perimeter of a rectangle, we add the length and width of rectangle and then multiply it with 2. In other words, perimeter is the addition of length of all the sides of a rectangle.

Note: Perimeter of a Rectangle is calculated using the formula
Perimeter = 2 * (Length + Width);

Length: is the length of the longest side of the rectangle.
width: is the length of the smallest side of the rectangle.

Find Perimeter of a Rectangle: C Program

[youtube https://www.youtube.com/watch?v=EnQTDhvimd0]

YouTube Link: https://www.youtube.com/watch?v=EnQTDhvimd0 [Watch the Video In Full Screen.]

Source Code: Find Perimeter of a Rectangle: C Program

#include < stdio.h >

int main()
{
    float length, width, perimeter;

    printf("Enter length of Rectangle\n");
    scanf("%f", &length);

    printf("Enter width of Rectangle\n");
    scanf("%f", &width);

    perimeter = 2 * (length + width);

    printf("Perimeter of Rectangle is %f\n", perimeter);

    return 0;
}

Output:
Enter length of Rectangle
12
Enter width of Rectangle
6
Perimeter of Rectangle is 36.000000

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Area of Rectangle: C Program

The length and breadth / width of a rectangle are entered through the keyboard. Write a program to calculate the area of the rectangle.

Rectangle is a quadrilateral(i.e., it has 4 sides). And all the 4 angles of the rectangle are of 90 degree. To calculate area of a rectangle we need its length and width/breadth.

Note: Area of a Rectangle is calculated using the formula
Area = Length * Width;

Length: is the length of the longest side of the rectangle.
width: is the length of the smallest side of the rectangle.

Find Area of a Rectangle: C Program

[youtube https://www.youtube.com/watch?v=yvgxG0hGqsY]

YouTube Link: https://www.youtube.com/watch?v=yvgxG0hGqsY [Watch the Video In Full Screen.]

Source Code: Find Area of a Rectangle: C Program

#include < stdio.h >

int main()
{
    float length, width, area;

    printf("Enter length of rectangle\n");
    scanf("%f", &length);

    printf("Enter width of rectangle\n");
    scanf("%f", &width);

    area = length * width;

    printf("Area of Rectangle is %f\n", area);

    return 0;
}

Output:
Enter length of rectangle
12
Enter width of rectangle
6
Area of Rectangle is 72.000000

For list of all c programming interviews / viva question and answers visit: C Programming Interview / Viva Q&A List

For full C programming language free video tutorial list visit:C Programming: Beginner To Advance To Expert

Simple Animation using Canvas: HTML5

Today lets see how we can do simple animation using Canvas.

Demo

Here we draw a circle and move it from starting point of x-axis to the end of the canvas.

index.html and myStyle.css file content are same as Linear Gradients in Canvas: HTML5

JavaScript file: Moving Circle Code
myScript.js

context.beginPath();
context.fillStyle = "red";
context.arc(x++, context.canvas.height/2, r, 0, 2 * Math.PI);
context.fill();

Here I’m drawing a circle with a red fill and incrementing it’s x-axis value each time it is called.

JavaScript file: x-axis movement control
myScript.js

var r = 50;
var x = -r;
 
if( x >= context.canvas.width + r)
    x  = -r;

Here the x-axis value is tracked each time and is set back to -50 ( minus radius of the circle ) once the circle moves out of the x-axis or the canvas width.

Simple Animation using Canvas: HTML5

[youtube https://www.youtube.com/watch?v=iyGQhumPgcc]

YouTube Link: https://www.youtube.com/watch?v=iyGQhumPgcc [Watch the Video In Full Screen.]

JavaScript file: Full Free Source Code
myScript.js

window.onload = canvas;
 
function canvas()
{
var myCanvas = document.getElementById("myCanvas");
 
if( myCanvas && myCanvas.getContext("2d") ) 
{
var context         = myCanvas.getContext("2d");
var r = 50;
var x = -r;
 
setInterval(function(){
context.fillStyle   = "#000";
context.fillRect(0, 0, context.canvas.width, context.canvas.height);
 
context.beginPath();
context.fillStyle   = "red";
context.arc(x++, context.canvas.height/2, r, 0, 2 * Math.PI);
context.fill();
 
if( x >= context.canvas.width + r)
    x  = -r; 
}, 10);
}
}

Here we use the setInterval() method to iterate/loop through the anonymous function and each time the background of the canvas is set to black(#000 or #000000) by drawing a black rectangle across the entire canvas width and height. For every call the value of x increments by 1, hence the circle moves 1px away from its previous position, until it reaches the end of canvas – after which it is reset back to -r value.