Javascript Articles - Page 257 of 534

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]

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

We are required to write a JavaScript function that takes in a string and returns the shortest word from the string.For example: If the input string is −const str = 'This is a sample string';Then the output should be −const output = 'a';ExampleThe code for this will be −const str = 'This is a sample string'; const findSmallest = str => {    const strArr = str.split(' ');    const creds = strArr.reduce((acc, val) => {       let { length, word } = acc;       if(val.length < length){          length = val.length;   ... Read More

Suppose we have a JSON object that have information about the location of some cities of some countries like this −const countryInfo = {    country: [{       name: "Bangladesh",       province: [{          name:"Dhaka",          city: [{             name:"Tangail",             lat: '11'          }, {             name:"Jamalpur",             lat: '12'          }]       }, {          name: "Khulna", ... Read More

We are given two arrays: (arr1 and arr2) −arr1 contains some literal values.arr2 contains objects that map some literal values.We are required to write a JavaScript function that takes in two such arrays. Then the function should return an array of all the elements from arr1 that are not mapped by objects in arr2.ExampleThe code for this will be −const arr1 = [111, 222, 333, 444]; const arr2 = [    { identifier: 111 },    { identifier: 222 },    { identifier: 444 }, ]; const getAbsentValues = (arr1, arr2) => {    let res = [];    res = arr1.filter(el => {       return !arr2.find(obj => {          return el === obj.identifier;       });    });    return res; }; console.log(getAbsentValues(arr1, arr2));OutputThe output in the console −[ 333 ]

We are required to write a JavaScript function that takes in an array of Numbers as the first argument and a number, say n as the second argument. The number n will always be less than or equal to the length of the array.Our function should return an array of the sum of all elements of all the possible subarrays of length n from the original array.For example, If the input is −const arr = [2, 6, 4]; const n = 2;Then the output should be −const output = [8, 10, 6];ExampleThe code for this will be −const arr = ... Read More