Javascript Articles - Page 222 of 607

Modify an array based on another array JavaScript

AmitDiwan
Updated on 25-Nov-2020 04:57:14

986 Views

Suppose, we have a reference array of phrases like this −const reference = ["your", "majesty", "they", "are", "ready"];And we are required to join some of the elements of above array based on another array so if another array is this −const another = ["your", "they are"];The result would be like −result = ["your", "majesty", "they are", "ready"];Here, we compared the elements in both the arrays, we joined the elements of the first array if they existed together in the second array.We are required to write a JavaScript function that takes in two such arrays and returns a new joined array.Exampleconst ... Read More

Fuzzy Search Algorithm in JavaScript

AmitDiwan
Updated on 25-Nov-2020 04:55:12

1K+ Views

We are required to write a JavaScript String function that takes in a search string can loosely checks for the search string in the string it is used with.The function should take this criterion into consideration: It should loop through the search query letters and check if they occur in the same order in the string.For example −('a haystack with a needle').fuzzySearch('hay sucks'); // false ('a haystack with a needle').fuzzySearch('sack hand'); // trueExampleconst fuzzySearch = function (query) {    const str = this.toLowerCase();    let i = 0, n = -1, l;    query = query.toLowerCase();    for (; l ... Read More

Longest decreasing subsequence subarray in JavaScript

AmitDiwan
Updated on 25-Nov-2020 04:53:54

253 Views

We are required to write a JavaScript function that takes in an array of Integers. The function should return the length of the longest decreasing subsequence from the array.For example −If the input array is −const arr = [5, 2, 5, 4, 3, 2, 4, 6, 7];Then the output should be −const output = 4;because the longest decreasing subsequence (of consecutive words) is [5, 4, 3, 2];Exampleconst arr = [5, 2, 5, 4, 3, 2, 4, 6, 7]; const decreasingSequence = (arr = []) => {    let longest = [];    let curr = [];    const setDefault = ... Read More

Finding all possible combined (plus and minus) sums of n arguments JavaScript

AmitDiwan
Updated on 25-Nov-2020 04:52:35

367 Views

We are required to write a JavaScript function that in any number of arguments (all of Number type).The function should calculate all possible sums of addition and subtraction.For example − If the arguments are 1, 2, 3Then all possible combinations are −1 + 2 + 3 1 - 2 - 3 1 + 2 - 3 1 - 2 + 3Finally, the function should the sum that is closest to 0. In this case, that answer would just be 0.Exampleconst findSmallestPositive = (...arr) => {    let set = new Set([Math.abs(arr[0])]);    for (let i = 1;    i < ... Read More

Find first duplicate item in array in linear time JavaScript

AmitDiwan
Updated on 25-Nov-2020 04:51:22

332 Views

We are required to write a JavaScript function that takes in a read only array of n + 1 integers between 1 and n.The function should find one number that repeats in linear time and using at most O(n) space.For example If the input array is −const arr = [3 4 1 4 1];Then the output should be −const output = 1;If there are multiple possible answers ( like above ), we should output any one. If there is no duplicate, we should output -1.Exampleconst arr = [3, 4, 1, 4, 1]; const findRepeatedNumber = (arr = []) => { ... Read More

JavaScript Quicksort Recursive

Alshifa Hasnain
Updated on 17-Jan-2025 19:47:24

1K+ Views

In this article, we will learn to implement Quicksort recursively in JavaScript. Quicksort is one of the most efficient and widely used sorting algorithms, known for its divide-and-conquer approach. What is Quicksort? Quicksort is a divide-and-conquer sorting algorithm that sorts an array by selecting a pivot element and partitioning the array into two subarrays: elements smaller than the pivot and elements greater than or equal to the pivot. It then recursively sorts the subarrays.  Algorithm Quicksort follows the below steps − Step 1 − Make any element the pivot (preferably first or last, ... Read More

JavaScript - summing numbers from strings nested in array

AmitDiwan
Updated on 24-Nov-2020 11:06:51

208 Views

Suppose, we have an array that contains some demo credit card numbers like this −const arr = ['4916-2600-1804-0530', '4779-252888-3972', '4252-278893-7978', '4556-4242-9283-2260'];We have been tasked with creating a function that takes in this array. The function must return the credit card number with the greatest sum of digits.If two credit card numbers have the same sum, then the last credit card number should be returned by the function.ExampleThe code for this will be −const arr = ['4916-2600-1804-0530', '4779-252888-3972', '4252-278893-7978', '4556-4242-9283-2260']; const findGreatestNumber = (arr) => {    let n, i = 0, sums;    sums = [];    while (i < ... Read More

Convert array of object to array of array in JavaScript

AmitDiwan
Updated on 24-Nov-2020 11:06:01

2K+ Views

Suppose, we have the following array of objects −const arr = [    {"2015":11259750.05},    {"2016":14129456.9} ];We are required to write a JavaScript function that takes in one such array. The function should prepare an array of arrays based on the input array.Therefore, the output for the above array should look like −const output = [    [2015,11259750.05],    [2016,14129456.9] ];ExampleThe code for this will be −const arr = [    {"2015":11259750.05},    {"2016":14129456.9} ]; const mapToArray = (arr = []) => {    const res = [];    arr.forEach(function(obj,index){       const key= Object.keys(obj)[0];       const value = parseInt(key, 10);       res.push([value, obj[key]]);    });    return res; }; console.log(mapToArray(arr));OutputAnd the output in the console will be −[ [ 2015, 11259750.05 ], [ 2016, 14129456.9 ] ]

Enter a number and write a function that adds the digits together on button click in JavaScript

AmitDiwan
Updated on 24-Nov-2020 11:04:53

646 Views

We are required to write a JavaScript program that provides users an input to fill in a number.And upon filling when the user clicks the button, we should display the sum of all the digits of the number.ExampleThe code for this will be −JavaScript Code −function myFunc() {    var num = document.getElementById('digits').value;    var tot = 0;    num.split('').forEach( function (x) {       tot = tot + parseInt(x,10);    }); document.getElementById('output').innerHTML = tot; }HTML Code − Submit OutputAnd the output will be &miuns;After clicking “Submit” −

Alphanumeric sorting using JavaScript

AmitDiwan
Updated on 24-Nov-2020 10:58:22

439 Views

We have a mixed array that we need to sort by alphabet and then by digit −const arr = ['Ab-1', 'Ab-11', 'Ab-12', 'ab-10', 'ab-100', 'ab-101', 'ab2', 'ab-3', 'ab-105'];ExampleThe code for this will be −const arr = ['Ab-1', 'Ab-11', 'Ab-12', 'ab-10', 'ab-100', 'ab-101', 'ab2', 'ab-3', 'ab-105']; const alphaNumericSort = (arr = []) => {    arr.sort((a, b) => {       const aPart = a.split('-');       const bPart = b.split('-');       return aPart[0].toLowerCase().localeCompare(bPart[0].toLowerCase()) || aPart[1] - bPart[1];    }); }; alphaNumericSort(arr); console.log(arr);OutputAnd the output in the console will be −[    'Ab-1', 'ab-2',    'ab-3', 'ab-10', ... Read More

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