Front End Technology Articles - Page 318 of 652

We are required to write a JavaScript function that takes in a string that contains some one-digit numbers in between and the function should return the sum of all the numbers present in the string.ExampleThe code for this will be −const str = 'uyyudfgdfgf5jgdfj3hbj4hbj3jbb4bbjj3jb5bjjb5bj3'; const sumNum = str => {    const strArr = str.split("");    let res = 0;    for(let i = 0; i < strArr.length; i++){       if(+strArr[i]){          res += +strArr[i];       };    };    return res; }; console.log(sumNum(str));OutputThe output in the console −35

We are required to write a JavaScript function that takes in an array of numbers and returns the alternative multiplicative sum of the elements.For example: If the array is −const arr = [1, 2, 3, 4, 5, 6, 7];Then the output should be calculated like this −1*2+3*4+5*6+7 2+12+30+7And the output should be −51Let’s write the code for this function −ExampleThe code for this will be −const arr = [1, 2, 3, 4, 5, 6, 7]; const alternateOperation = arr => {    const productArr = arr.reduce((acc, val, ind) => {       if(ind % 2 === 1){          return acc;       };       acc.push(val * (arr[ind + 1] || 1));       return acc;    }, []);    return productArr.reduce((acc, val) => acc + val); }; console.log(alternateOperation(arr));OutputThe output in the console −51

Suppose, we have an object like this −const obj = {    name: "Jai",    age: 32,    occupation: "Software Engineer",    address: "Dhindosh, Maharasthra",    salary: "146000" };We are required to write a JavaScript function that takes in such an object with key value pairs and converts it into a Map.ExampleThe code for this will be −const obj = {    name: "Jai",    age: 32,    occupation: "Software Engineer",    address: "Dhindosh, Maharasthra",    salary: "146000" }; const objectToMap = obj => {    const keys = Object.keys(obj);    const map = new Map();    for(let i = ... Read More

ASCII Code:ASCII is a 7-bit character code where every single bit represents a unique character. Every English alphabet has a unique decimal ascii code.We are required to write a function that takes in two strings and calculates their ascii scores (i.e., the sum of ascii decimal of each character of string) and returns the difference.Let’s write the code for this function −ExampleThe code for this will be −const str1 = 'This is an example sting'; const str2 = 'This is the second string'; const calculateScore = (str = '') => {    return str.split("").reduce((acc, val) => {       ... Read More

We are required to write a JavaScript function that takes in two numbers, say, a and b and returns the total number of prime numbers between a and b (including a and b, if they are prime).For example: If a = 21, and b = 38.The prime numbers between them are 23, 29, 31, 37And their count is 4Our function should return 4ExampleThe code for this will be −const isPrime = num => {    let count = 2;    while(count < (num / 2)+1){       if(num % count !== 0){          count++;          continue;       };       return false;    };    return true; }; const primeBetween = (a, b) => {    let count = 0;    for(let i = Math.min(a, b); i

We are required to write a JavaScript function that takes in a string and a number, say k and returns another string with first k characters removed from the string.For example: If the original string is −const str = "this is a string"and, n = 4then the output should be −const output = " is a string"ExampleThe code for this will be −const str = 'this is a string'; const removeN = (str, num) => {    const { length } = str;    if(num > length){       return str;    };    const newStr = str.substr(num, length ... Read More

We are required to write a JavaScript function that takes in two strings and concatenates the second string to the first string.If the last character of the first string and the first character of the second string are the same then we have to omit one of those characters.ExampleThe code for this will be −const str1 = 'Food'; const str2 = 'dog'; const concatenateStrings = (str1, str2) => {    const { length: l1 } = str1;    const { length: l2 } = str2;    if(str1[l1 - 1] !== str2[0]){       return str1 + str2;    }; ... Read More

We are required to write a JavaScript function that takes in a number and returns a boolean based on the fact whether or not the number is a perfect square.Examples of perfect square numbers −Some perfect square numbers are −144, 196, 121, 81, 484ExampleThe code for this will be −const num = 484; const isPerfectSquare = num => {    let ind = 1;    while(ind * ind

We are required to write a JavaScript function that takes in an array of numbers and returns the cumulative sum of every number present at the index that is a multiple of n from the array.ExampleThe code for this will be −const arr = [5, 3, 5, 6, 12, 5, 65, 3, 2]; const num = 3; const nthSum = (arr, num) => {    let sum = 0;    for(let i = 0; i < arr.length; i++){       if(i % num !== 0){          continue;       };       sum += arr[i];    };    return sum; }; console.log(nthSum(arr, num));OutputThe output in the console −76

We are required to write a JavaScript function that takes in an array of Number. Then the function should return the average of its elements excluding the smallest and largest Number.ExampleThe code for this will be −const arr = [5, 3, 5, 6, 12, 5, 65, 3, 2]; const findExcludedAverage = arr => {    const creds = arr.reduce((acc, val) => {       let { min, max, sum } = acc;       sum += val;       if(val > max){          max = val;       };       if(val < min){          min = val;       };       return { min, max, sum };    }, {       min: Infinity,       max: -Infinity,       sum: 0    });    const { max, min, sum } = creds;    return (sum - min - max) / (arr.length / 2); }; console.log(findExcludedAverage(arr));OutputThe output in the console −8.666666666666666