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We're a place where coders share, stay up-to-date and grow their careers. # Day 1 - 10DaysOfJavaScript Deepak Raj Updated on ・2 min read ### 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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## Discussion (9)  pentacular

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() {