Loop Backward in Array of Objects in JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:46:30

166 Views

We have an array of objects like this −let data = [    {id:1, Name: "Abe", RowNumber: 1 },    {id:2, Name: "Bob", RowNumber: 2 },    {id:3, Name: "Clair", RowNumber: 3 },    {id:4, Name: "Don", RowNumber: 3.0 },    {id:5, Name: "Edna", RowNumber: 3.1 },    {id:6, Name: "Frank", RowNumber: 3.2 },    {id:7, Name: "Gabe", RowNumber: 4 },    {id:8, Name: "Helen", RowNumber: 5 },    {id:9, Name: "Isabelle", RowNumber: 6 },    {id:10, Name: "Jane", RowNumber: 7 },    {id:11, Name: "Ken", RowNumber: 8 }, ];We are required to write a JavaScript function that takes in ... Read More

Search and Update Array Based on Key in JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:41:43

206 Views

We have two arrays like these −let arr1 = [{"LEVEL":4, "POSITION":"RGM"}, {"LEVEL":5, "POSITION":"GM"}, {"LEVEL":5, "POSITION":"GMH"}] let arr2 = [{"EMAIL":"test1@stc.com", "POSITION":"GM"}, {"EMAIL":"test2@stc.com", "POSITION":"GMH"}, {"EMAIL":"test3@stc.com", "POSITION":"RGM"}, {"EMAIL":"test3@CSR.COM.AU", "POSITION":"GM"} ]We are required to write a function that adds the property level to each object of arr2, picking it up from the object from arr1 that have the same value for property "POSITION"Let's write the code for this function −Examplelet arr1 = [{"LEVEL":4, "POSITION":"RGM"}, {"LEVEL":5, "POSITION":"GM"}, {"LEVEL":5, "POSI TION":"GMH"}]    let arr2 = [{"EMAIL":"test1@stc.com", "POSITION":"GM"},    {"EMAIL":"test2@stc.com", "POSITION":"GMH"},    {"EMAIL":"test3@stc.com", "POSITION":"RGM"},    {"EMAIL":"test3@CSR.COM.AU", "POSITION":"GM"} ] const formatArray = (first, second) => {    second.forEach((el, ... Read More

Split Last N Digits of Each Value in Array with JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:39:47

318 Views

We have an array of literals like this −const arr = ["", 20191219, 20191220, 20191221, 20191222, 20191223, 20191224, 20191225];We are required to write a JavaScript function that takes in this array and a number n and if the corresponding element contains more than or equal to n characters, then the new element should contain only the last n characters otherwise the element should be left as it is.Let's write the code for this function −Exampleconst arr = ["", 20191219, 20191220, 20191221, 20191222, 20191223, 20191224, 20191225]; const splitElement = (arr, num) => {    return arr.map(el => {       if(String(el).length

Return an Array Containing All Strings from Subarrays in JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:37:24

305 Views

We have an array of arrays like this −const arr = [    ['foo', 'bar', 'hey', 'oi'],    ['foo', 'bar', 'hey'],    ['foo', 'bar', 'anything'],    ['bar', 'anything'] ]We are required to write a JavaScript function that takes in such array and returns an array that contains all the strings which appears in all the subarrays.Let's write the code for this functionExampleconst arr = [    ['foo', 'bar', 'hey', 'oi'],    ['foo', 'bar', 'hey'],    ['foo', 'bar', 'anything'],    ['bar', 'anything'] ] const commonArray = arr => {    return arr.reduce((acc, val, index) => {       return acc.filter(el => val.indexOf(el) !== -1);    }); }; console.log(commonArray(arr));OutputThe output in the console will be −['bar']

Reverse Numbers in Function without Using Reverse Method in JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:32:48

1K+ Views

We are required to write a JavaScript function that takes in a number and returns its reversed number with converting it to an array or string.Let's write the code for this function −Exampleconst num = 234567; const reverseNumber = (num, res = 0) => {    if(num){       return reverseNumber(Math.floor(num / 10), (res*10)+(num % 10));    };    return res; }; console.log(reverseNumber(num)); console.log(reverseNumber(53536)); console.log(reverseNumber(76576));OutputThe output in the console will be −765432 63535 67567

Maximum Products of Two Integers in Linear Time in JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:29:48

149 Views

We are required to write a JavaScript function that takes in an array of Numbers with positive as well as negative numbers and returns the maximum products of two numbers in one traversal.Let's write the code for this function −Exampleconst arr = [-1, -3, -4, 2, 0, -5]; const arr2 = [2, 3, 5, 7, -7, 5, 8, -5]; const produce = arr => arr.reduce((acc, val) => acc*val); const maximumProduct = (arr = []) => {    const [first] = arr;    if(!first){       return 0;    };    const creds = arr.reduce((acc, val) => {     ... Read More

Separate Odd and Even Numbers in JavaScript

AmitDiwan
Updated on 31-Aug-2020 13:02:05

760 Views

We are required to write a JavaScript function that takes in an array of numbers and returns an array with all even numbers appearing on the left side of any odd number and all the odd numbers appearing on the right side of any even number.Therefore, let's write the code for this function −Exampleconst arr = [2, 6, 3, 7, 8, 3, 5, 4, 3, 6, 87, 23, 2, 23, 67, 4]; const isEven = num => num % 2 === 0; const sorter = (a, b) => {    if(isEven(a) && !isEven(b)){       return -1;    };    if(!isEven(a) && isEven(b)){       return 1;    };    return 0; }; arr.sort(sorter); console.log(arr);OutputThe output in the console will be −[    2, 6, 8, 4, 6, 2,    4, 3, 7, 3, 5, 3,    87, 23, 23, 67 ]

Wildcard Matching of String in JavaScript

AmitDiwan
Updated on 31-Aug-2020 12:51:07

2K+ Views

We are required to write a JavaScript function that accepts two strings and a number n. The function matches the two strings i.e., it checks if the two strings contains the same characters. The function should return true if both the strings contain the same character irrespective of their order or if they contain at most n different characters, otherwise the function should return false.Let's write the code for this function −Exampleconst str1 = 'first string'; const str2 = 'second string'; const wildcardMatching = (first, second, num) => {    let count = 0;    for(let i = 0; i ... Read More

Object Difference in JavaScript

AmitDiwan
Updated on 31-Aug-2020 12:48:57

148 Views

We are required to write a JavaScript function that takes in two objects (possibly nested) and returns a new object with key value pair for the keys that were present in the first object but not in the secondLet's write the code for this function −Exampleconst obj1 = {    "firstName": "Raghav",    "lastName": "Raj",    "age": 43,    "address": "G-12 Kalkaji",    "email": "raghavraj1299@yahoo.com",    "salary": 90000 }; const obj2 = {    "lastName": "Raj",    "address": "G-12 Kalkaji",    "email": "raghavraj1299@yahoo.com",    "salary": 90000 }; const objectDifference = (first, second) => {    return Object.keys(first).reduce((acc, val) => { ... Read More

Rearrange String So That Same Characters Are N Distance Apart in JavaScript

AmitDiwan
Updated on 31-Aug-2020 12:46:33

275 Views

We are required to write a JavaScript function that takes in a string with repetitive characters and returns a new string in which all the same characters are exactly n characters away from each other. And the number should be smaller than the length of the array.For example −If the input string is: "accessories" And the number n is 3 Then, The return value should be: "secrsecisao"Note − There may be some other permutation to achieve the required output, the order is not important, we should stick to the logic and as long as we fulfil it our output is ... Read More

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