## DEV Community is a community of 695,260 amazing developers

We're a place where coders share, stay up-to-date and grow their careers. # Day 1 - 10DaysOfJavaScript Deepak Raj
Skilled in Data Science, Machine Learning, Deep Learning, As Well As Web Development Knowledge. React ❤️ to encourage Author. ### Day 1: Arithmetic Operators

• A length and width are sent to two different functions
• getArea must return the area of the shape dimensions sent
• getPerimeter must return the perimeter of the shape dimensions sent
• Complete the functions
``````/**
*   Calculate the area of a rectangle.
*
*   length: The length of the rectangle.
*   width: The width of the rectangle.
*
*  Return a number denoting the rectangle's area.
**/
function getArea(length, width) {
let area;
area = length * width;
return area;
}

/**
*   Calculate the perimeter of a rectangle.
*
*  length: The length of the rectangle.
*   width: The width of the rectangle.
*
*  Return a number denoting the perimeter of a rectangle.
**/
function getPerimeter(length, width) {
let perimeter;
perimeter = 2 * (length + width);
return perimeter;
}
``````

### Day 1: Functions

• A integer of value n is provided
• 1 ≤ n ≤ 10
• Output the factorial value of n (n!, 4! = 4 x 3 x 2 x 1 = 24)
``````/*
* Create the function factorial here
* Recursion: To call itself is called recursion.
*/
function factorial(n) {
if (n === 0) {
return 1;
}
return n * factorial(n - 1);
}
``````

### Day 1: Let and Const

• A float value r is provided for the radius
• 0 < r ≤ 100
• Print (console.log) the area of the circle (π x r²)
• Print (console.log) the perimeter of the circle (2πr)
• Do not overwrite the try and catch but make sure the code still works
``````function main() {
const PI = Math.PI;
// Print the area of the circle:
console.log(PI * (r * r) );
// Print the perimeter of the circle:
console.log(2 * PI * r);
}
``````

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React ❤️ to encourage Author.

## Discussion (9) Consider not using unnecessary variables.

``````function getArea(length, width) {
return length * width;
}
``````

const is about the variable, not the value, so r should be const as you do not reassign it.

``````function main() {
...
}
`````` Deepak Raj • Edited

The Above Code are from HackerRank. Some of code are autogenerated. Changing in some code mislead.

Check more at HackerRank Deepak Raj

I am learning JavaScript and it's for encourage Other as well. Deepak Raj • Edited

Some of code are autogenerated, you have to only write logic according to question and complete the challenge. It's like Leet code but has Boilerplate code for beginners.

You can find an Example here 👇👇

hackerrank.com/challenges/js10-try...

Happy Coding 😀  