flattenArray.js

/*
 * The below code flattens an arbitrarily nested arrays 
 * eg:-  [1,2,[3]],4] -> [1,2,3,4]
 */

//User Input - Array that is to be flattened
var arrInput = [[1,2,[3]],4]

/*
 * Method to flatten an array
 * It converts the complete array into a string which will be comma separated
 * using the toString native javascript method & then splits using operator ','
 */
var getFlattenedArray = function getFlattenedArray(arrInput) {
	return arrInput.toString().split(',')
}

//Output - Flattened array
var flattenedArray = getFlattenedArray(arrInput)
console.log(flattenedArray)	//Prints the flattened array