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Basic JavaScript: Replace Loops using Recursion
Recursion is the concept that a function can be expressed in terms of itself. To help understand this, start by thinking about the following task: multiply the first n elements of an array to create the product of those elements. Using a for loop, you could do this:

function multiply(arr, n) {
var product = 1;
for (var i = 0; i < n; i++) {
product *= arr[i];
}
return product;
}
However, notice that multiply(arr, n) == multiply(arr, n - 1) * arr[n - 1]. That means you can rewrite multiply in terms of itself and never need to use a loop.

function multiply(arr, n) {
if (n <= 0) {
return 1;
} else {
return multiply(arr, n - 1) * arr[n - 1];
}
}
The recursive version of multiply breaks down like this. In the base case, where n <= 0, it returns 1. For larger values of n, it calls itself, but with n - 1. That function call is evaluated in the same way, calling multiply again until n <= 0. At this point, all the functions can return and the original multiply returns the answer.****

@jyoti-wp
Please complete these exercises:

1. Create a file called challenge.js in your html directory.
2. Include this javascript file in your index.html, just before ends, like so:
   <script src="challenge.js"></script>

• Exercise 1: Write a variable called age and its value should be 60;

• Exercise 2: Write an if, else condition, that should console.log( 'old' ); if the value of age variable is greater than 50, else it should console.log( 'not old' );

• Exercise 3: Create a variable called day whose value should be 'Saturday', then 'Write a function that console.log('weekend'); if the value of day is 'Saturday' or 'Sunday'