Let's say we have a variable “users” that contains the following string of text where each user is separated by a semicolon and each attribute of each users is separated by a comma −const users = 'Bob, 1234, Bob@example.com;Mark, 5678, Mark@example.com';We are required to write a JavaScript function that takes in one such string and splits this into a multidimensional array that looks like this −const arr = [    ['Bob', 1234, 'Bob@example.com'],    ['Mark', 5678, 'Mark@example.com'] ];ExampleThe code for this will be −const users = 'Bob, 1234, Bob@example.com;Mark, 5678, Mark@example.com'; const splitByPunctuations = (str = '') => {   ... Read More

This problem takes its name by arguably the most important event in the life of the ancient historian Josephus − according to his tale, he and his 40 soldiers were trapped in a cave by the Romans during a siege.Refusing to surrender to the enemy, they instead opted for mass suicide, with a twist − they formed a circle and proceeded to kill one man every three, until one last man was left (and that it was supposed to kill himself to end the act).Josephus and another man were the last two and, as we now know every detail of ... Read More

Suppose we have a number, const num = 76;However, If we round off this number to nearest 10 place, the result will be 80If we round off this number to nearest 100 place, the result will be 100If we round off this number to nearest 1000 place, the result will be 0We are required to write a JavaScript function that takes in a number to be rounded as the first argument and the rounding off factor as the second argument.The function should return the result after rounding off the number.ExampleThe code for this will be −const num = 76; const ... Read More

Suppose we have an array of objects that contains the data about some students and their marks like this −const arr = [    { subject: 'Maths', marks: '40', noOfStudents: '5' },    { subject: 'Science', marks: '50', noOfStudents: '16' },    { subject: 'History', marks: '35', noOfStudents: '23' },    { subject: 'Science', marks: '65', noOfStudents: '2' },    { subject: 'Maths', marks: '30', noOfStudents: '12' },    { subject: 'History', marks: '55', noOfStudents: '20' }, ];We are required to write a JavaScript function that takes in one such array.The function should eliminate the redundant entries on the basis ... Read More

Suppose we have a JSON object like this −const obj = {    "LAPTOP": [{       "productId": "123"    }],    "DESKTOP": [{       "productId": "456"    }],    "MOUSE": [{       "productId": "789"    }, {       "productId": "012"    }],    "KEY-BOARD": [{       "productId": "345"    }] };We are required to write a JavaScript function that takes in one such object as the first argument, and a key value pair as the second argument.The key value pair is basically nothing but an object like this −const pair ... Read More

We are required to write a JavaScript function that takes in two numbers specifying a range. Our function should return a random prime number that falls in that rangeExampleThe code for this will be −const range = [100, 1000]; const getPrimes = (min, max) => {    const result = Array(max + 1)    .fill(0)    .map((_, i) => i);    for (let i = 2; i {    return Math.floor(Math.random() * (max − min + 1) + min); }; const getRandomPrime = ([min, max]) => {    const primes = getPrimes(min, max);    return primes[getRandomNum(0, primes.length − 1)]; }; console.log(getRandomPrime(range));OutputAnd the output in the console will be −311Output is likely to differ in each run.

Suppose we have an array of true/false represented by 't'/'f' which we retrieved from some database like this −const arr = ['f', 't', 'f', 't', 't', 't', 'f', 'f', 't', 't', 't', 't', 't', 't', 'f', 't'];We are required to write a JavaScript function that takes in one such array. Our function should count the consecutive appearances of those 't' that are sandwiched between two 'f's and return an array of that count.Therefore, for the above array, the output should look like −const output = [1, 3, 6, 1];ExampleThe code for this will be −const arr = ['f', 't', 'f', ... Read More

We are required to write a JavaScript function that takes in two strings, say str1 and str2. The function should then count and return the number of times str2 appears in str1'For example −count('this is a string', 'is') should return 2;ExampleThe code for this will be −const str1 = 'this is a string'; const str2 = 'is'; const countOccurrences = (str1, str2, allowOverlapping = true) => {    str1 += "";    str2 += "";    if (str2.length = 0) {          ++n;          pos += step;       } else break;    }    return n; }; console.log(countOccurrences(str1, str2));OutputAnd the output in the console will be −2

Suppose we have an array of arrays that contains the marks of some students in some subjects like this −const arr = [ ["English", 52], ["Hindi", 154], ["Hindi", 241], ["Spanish", 10], ["French", 65], ["German", 98], ["Russian", 10] ];We are required to write a JavaScript function that takes in one such array and returns an object of objects.The return object should contain an object for each unique subject, and that object should contain information like the number of appearances of that language, sum of total marks and the average.ExampleThe code for this will be −const arr = [    ["English", 52], ... Read More

In this tutorial, we will learn how to do a case-insensitive string comparison of strings in JavaScript. Case in-sensitive simply means the word or string should mean the same even if they are written in lower or upper case. In this kind of case in-sensitive comparison is observed in the google search bar, wherein if the user type “tUtoriAlsPOint” or “Tutorialspoint” the results are the same, similarly it is used in search bar too. There are 4 ways to do this, toUpperCase() toLowerCase() localeCompare() RegExp() Using the toUpperCase() Method When we use the toUpperCase() method on a string, ... Read More