## Algorithm

Hacker Rank problem link - https://www.hackerrank.com/challenges/js10-let-and-const/problem

Hackerrank problem details -

Objective

In this challenge, we practice declaring variables using the let and const keywords. Check out the attached tutorial for more details.

1. Declare a constant variable, and assign it the value Math.PI. You will not pass this challenge unless the variable is declared as a constant and named PI (uppercase).
2. Read a number, , denoting the radius of a circle from stdin.
3. Use  and  to calculate the  and  of a circle having radius .
4. Print  as the first line of output and print  as the second line of output.

Input Format

A single integer, , denoting the radius of a circle.

Constraints

•  is a floating-point number scaled to at most  decimal places.

Output Format

Print the following two lines:

1. On the first line, print the  of the circle having radius .
2. On the second line, print the  of the circle having radius .

Sample Input 0

2.6

Sample Output 0

21.237166338267002
16.336281798666924

Explanation 0

Given the radius , we calculate the following:

We then print  as our first line of output and  as our second line of output.

## Code Examples

### #1 Code Example with Javascript Programming

Code - Javascript Programming


//Main part
function main() {

let r, area, perimeter;
const PI = Math.PI;

// Print the area of the circle:
area = PI * r * r;
console.log(area);

// Print the perimeter of the circle:
perimeter = 2 * PI * r;
console.log(perimeter);

try {
// Attempt to redefine the value of constant variable PI
PI = 0;
// Attempt to print the value of PI
console.log(PI);
} catch(error) {
console.error("You correctly declared 'PI' as a constant.");
}
}

Copy The Code &

Input

cmd
2.6

Output

cmd
21.237166338267002
16.336281798666924