Found 8591 Articles for Front End Technology

Finding shortest word in a string in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:23:40

801 Views

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

Dynamic Programming: return all matched data in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:21:59

312 Views

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

Get values that are not present in another array in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:16:21

2K+ Views

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 ]

All combinations of sums for array in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:14:18

868 Views

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

Generate Ranking with combination of strings in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:10:15

286 Views

We are required to write a JavaScript function that takes in any number of arrays of numbers. Then the function should return an object that returns a frequency map indicating how many times each element has appeared checking in all the array.For example, If the arrays are −const a = [23, 45, 21], b = [45, 23], c = [21, 32], d = [23], e= [32], f=[50, 54];Then the output should be −const output = {    "21": 2,    "23": 3,    "32": 2,    "45": 2,    "52": 1,    "54": 1,    "23, 45": 2,    "23, ... Read More

How to iterate over objects in array and sum a property in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:07:14

865 Views

Suppose we have an array of objects like this −const arr = [    {       duration: 10,       any: 'fields'    }, {       duration: 20,       any: 'other fields'    }, {       duration: 15,       any: 'some other fields'    } ];We are required to write a JavaScript function that takes in one such array and returns the summed result of the duration properties of all the objects.For the above array, the output should be 45.ExampleThe code for this will be −const arr = [ ... Read More

Grouping names based on first letter in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:04:54

1K+ Views

Suppose, we have an array of names like this −const arr = ["Simon", "Mike", "Jake", "Lara", "Susi", "Blake", "James"];We are required to write a JavaScript function that takes in one such array. The function should return an array of objects with two properties −letter -> the letter on which the names are groupednames -> an array of names that falls in that groupExampleThe code for this will be −const arr = ["Simon", "Mike", "Jake", "Lara", "Susi", "Blake", "James"]; const groupNames = arr => {    const map = arr.reduce((acc, val) => {       let char = val.charAt(0).toUpperCase();   ... Read More

Filtering out only null values in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:02:46

383 Views

We are required to write a JavaScript function that takes in an array that contains some false values. The function should remove all the null values from the array (if there are any) in place.For example: If the input array is −const arr = [12, 5, undefined, null, 0, false, null, 67, undefined, false, null];Then the output should be −const output = [12, 5, undefined, 0, false, 67, undefined, false];ExampleThe code for this will be −const arr = [12, 5, undefined, null, 0, false, null, 67, undefined, false, null]; const removeNullValues = arr => {    for(let i = 0; ... Read More

Split Array by part base on N count in JavaScript

AmitDiwan
Updated on 10-Oct-2020 08:00:59

337 Views

We are required to write a JavaScript function that takes in an array of literals and a number, say n.The function should return a new array, chunked into n subarrays, given that n will always be less than or equal to the length of the array.For example: If the input array is −const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; const n = 3;Then the output should be −const output = [[1, 2, 3], [4, 5, 6], [7, 8, 9, 10]];ExampleThe code for this will be −const arr = [1, 2, 3, 4, 5, 6, ... Read More

Reversing words in a string in JavaScript

AmitDiwan
Updated on 10-Oct-2020 07:59:33

2K+ Views

We are required to write a JavaScript function that takes in a string. The function should return a new string that has all the words of the original string reversed.For example, If the string is −const str = 'this is a sample string';Then the output should be −const output = 'siht si a elpmas gnirts';ExampleThe code for this will be −const str = 'this is a sample string'; const reverseWords = str => {    let reversed = '';    reversed = str.split(" ")    .map(word => {       return word       .split("")       ... Read More

Advertisements