Suppose we have an array of literals like this −const arr = ['cat', 'dog', 'elephant', 'lion', 'tiger', 'mouse'];We are required to write a JavaScript function that takes in one such array as the first argument and then any number of strings as second and third and many more arguments.Then our function should remove all the strings from the array taken as first argument in place if that string is provided as argument to the function.ExampleThe code for this will be −const arr = ['cat', 'dog', 'elephant', 'lion', 'tiger', 'mouse']; const removeFromArray = (arr, ...removeArr) => {    removeArr.forEach(item => { ... Read More

We are required to write a JavaScript function that takes in two. Our function should then return a new array that contains characters alternatively from both the strings.For example: If the two strings are −const str1 = 'abc'; const str2 = 'def';OutputThen the output should be −const output = 'adbecf';ExampleThe code for this will be −const str1 = 'abc'; const str2 = 'def'; const mergeAlternatively = (str1, str2) => {    const a = str1.split("").filter(el => !!el);    const b = str2.split("");    let mergedString = '';    for(var i = 0; i < a.length || i < b.length; i++){ ... Read More

We are required to write a JavaScript function that takes in a two-dimensional array of literals.Our function should return a new array that contains all the entries from the original array but the repeating ones.ExampleThe code for this will be −const arr = [    [1,2,3,4,5],    [3,4,6,7,8,2],    [7,2,4,9,11,15],    [10,12,3,7,11] ]; const removeDuplicates = arr => {    let map = {};    let res = [];    res = arr.map(el => {       return el.filter(val => {          if(map[val]){             return false;          };          map[val] = 1;          return true;       });    });    return res; }; console.log(removeDuplicates(arr));OutputThe output in the console −[ [ 1, 2, 3, 4, 5 ], [ 6, 7, 8 ], [ 9, 11, 15 ], [ 10, 12 ] ]

We are required to write a JavaScript function that takes in an array of Numbers. Our function should return a new array that contains all the elements from the original array that are greater than the cumulative sum of all elements up to that point. We are required to solve this problem using the Array.prototype.reduce() function.ExampleLet’s write the code for this function −const arr = [1, 2, 30, 4, 5, 6]; const retainGreaterElements = arr => {    let res = [];    arr.reduce((acc, val) => {       return (val > acc && res.push(val), acc + val);    }, 0);    return res; } console.log(retainGreaterElements(arr));OutputThe output in the console −[1, 2, 30]

Suppose, we have an array of numbers like this −const arr = [1, 2, 3, 4, 5, 6];We are required to write a JavaScript function that takes in one such array and returns a new array with corresponding elements of the array being the sum of all the elements upto that point from the original array.Therefore, for the above array, the output should be −const output = [1, 3, 6, 10, 15, 21];ExampleThe code for this will be −const arr = [1, 2, 3, 4, 5, 6]; const findCumulativeSum = arr => {    const creds = arr.reduce((acc, val) => ... Read More

We are required to write a JavaScript function that takes a string and an array of strings.Our function should return a new string, where all the occurrences of the word in the string that are present in the array are replaced by a whitespace.Our function should use the String.prototype.replace() method to solve this problem.ExampleThe code for this will be −var excludeWords = ["A", "ABOUT", "ABOVE", "ACROSS", "ALL", "ALONG", "AM", "AN", "AND", "ANY", "ASK", "AT", "AWAY", "CAN", "DID", "DIDN'T", "DO", "DON'T", "FOR", "FROM", "HAD", "HAS", "HER", "HIS", "IN", "INTO", "IS", "IT", "NONE", "NOT", "OF", "ON", "One", "OUT", "SO", "SOME", "THAT", "THE", ... Read More

Suppose, we have an array of Numbers represented by strings like this −const arr = ["1.1", "1.2", "1.3", "2.1", "2.2", "3.1", "3.2", "3.3", "4.1", "4.2"];We are required to write a JavaScript function that takes in one such array and groups all the strings starting with same number in a common subarray.Therefore, the output of our function should look like −const output = [["1.1", "1.2", "1.3"], ["2.1", "2.2"], ["3.1", "3.2", "3.3"], ["4.1", "4.2"]];ExampleThe code for this will be −const arr = ["1.1", "1.2", "1.3", "2.1", "2.2", "3.1", "3.2", "3.3", "4.1", "4.2"]; const groupSimilarStarters = arr => {    let res = ... Read More

Suppose, we have an array of Numbers like this −const arr = [1, 2, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20];We are required to write a JavaScript function that takes in one such array and chunks the array into quarterly and yearly groups intermediately.The groups for the above array should look something like this −const quarterly = [[1, 2, 2], [4, 5, 6], [7, 8, 9], [10, 11, 12], [13, 14, 15], [16, 17, 18], [19, 20]]; const yearly = [[1, 2, 2, 4, 5, 6, 7, 8, 9, ... Read More

Suppose we have the number 12145. We are required to write a function that maps the digits of the number to English alphabets according to the following norms. The alphabets are to be mapped according to the 1 based index, like 'a' for 1 and 'b' for 2 'c' for 3 and so on.There can be several ways for mapping a number. Let's take the above number 121415 for example, It can be mapped as −12145->1, 2, 1, 4, 5->a, b, a, d, eIt also can be −12145->12, 1, 4, 5->l, a, d, eIt can also be −12145->12, 14, 5->l, ... Read More

Separating objects based on properties in JavaScript means rearranging a group of objects into a new structure where objects that share the same value for a specific property are placed together. Objects are collections of key-value pairs. It stores large data as a key with associated information as its value. In JavaScript, you often need to group objects inside a larger object based on certain properties. Separating objects based on properties in JavaScript can be done by writing a simple function using the reduce method. In this article, we will understand how to do this effectively. Understanding the Problem ... Read More