Javascript Articles - Page 355 of 607

The requirements here are simple, we are required to write a JavaScript function that takes in a number and returns the number of digits in it.For example −The number of digits in 4567 is 4 The number of digits in 423467 is 6 The number of digits in 457 is 3Let's write the code for this function −Exampleconst num = 2353454; const digits = (num, count = 0) => {    if(num){       return digits(Math.floor(num / 10), ++count);    };    return count; }; console.log(digits(num)); console.log(digits(123456)); console.log(digits(53453)); console.log(digits(5334534534));OutputThe output in the console will be −7 6 5 10

We are required to write a JavaScript function that takes in an array of Numbers and returns a new array with elements as the sum of two consecutive elements from the original array.For example, if the input array is −const arrayOne = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];Then the output should be −const newArrayOne = [1, 5, 9, 13, 17]Let's write the code for this function −Exampleconst arrayOne = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]; const doubleSum = arr => {    const res = [];    for(let i = 0; i < arr.length; i += 2){       res.push(arr[i] + (arr[i+1] || 0));    };    return res; }; console.log(doubleSum(arrayOne));OutputThe output in the console will be −[ 1, 5, 9, 13, 17 ]

We are required to write a JavaScript function that takes in two arrays of Numbers and checks whether all the elements of the first array exist in the second or not.Following are our arrays −const arr1 = [34, 78, 89]; const arr2 = [78, 67, 34, 99, 56, 89];Let's write the code and check for multiple values −Exampleconst arr1 = [34, 78, 89]; const arr2 = [78, 67, 34, 99, 56, 89]; const contains = (first, second) => {    const indexArray = first.map(el => {       return second.indexOf(el);    });    return indexArray.indexOf(-1) === -1; } console.log(contains(arr1, arr2));OutputThe output in the console will be −true

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

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

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

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']

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

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

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 ]