Suppose we have the number 12145. We are required to write a function that maps the digits of the number to English alphabets according to the following norms. The alphabets are to be mapped according to the 1 based index, like 'a' for 1 and 'b' for 2 'c' for 3 and so on.There can be several ways for mapping a number. Let's take the above number 121415 for example, It can be mapped as −12145->1, 2, 1, 4, 5->a, b, a, d, eIt also can be −12145->12, 1, 4, 5->l, a, d, eIt can also be −12145->12, 14, 5->l, ... Read More

Separating objects based on properties in JavaScript means rearranging a group of objects into a new structure where objects that share the same value for a specific property are placed together. Objects are collections of key-value pairs. It stores large data as a key with associated information as its value. In JavaScript, you often need to group objects inside a larger object based on certain properties. Separating objects based on properties in JavaScript can be done by writing a simple function using the reduce method. In this article, we will understand how to do this effectively. Understanding the Problem ... Read More

We are required to write a JavaScript function that takes in a string and returns the shortest word from the string.For example: If the input string is −const str = 'This is a sample string';Then the output should be −const output = 'a';ExampleThe code for this will be −const str = 'This is a sample string'; const findSmallest = str => {    const strArr = str.split(' ');    const creds = strArr.reduce((acc, val) => {       let { length, word } = acc;       if(val.length < length){          length = val.length;   ... Read More

Suppose we have a JSON object that have information about the location of some cities of some countries like this −const countryInfo = {    country: [{       name: "Bangladesh",       province: [{          name:"Dhaka",          city: [{             name:"Tangail",             lat: '11'          }, {             name:"Jamalpur",             lat: '12'          }]       }, {          name: "Khulna", ... Read More

We are given two arrays: (arr1 and arr2) −arr1 contains some literal values.arr2 contains objects that map some literal values.We are required to write a JavaScript function that takes in two such arrays. Then the function should return an array of all the elements from arr1 that are not mapped by objects in arr2.ExampleThe code for this will be −const arr1 = [111, 222, 333, 444]; const arr2 = [    { identifier: 111 },    { identifier: 222 },    { identifier: 444 }, ]; const getAbsentValues = (arr1, arr2) => {    let res = [];    res = arr1.filter(el => {       return !arr2.find(obj => {          return el === obj.identifier;       });    });    return res; }; console.log(getAbsentValues(arr1, arr2));OutputThe output in the console −[ 333 ]

We are required to write a JavaScript function that takes in an array of Numbers as the first argument and a number, say n as the second argument. The number n will always be less than or equal to the length of the array.Our function should return an array of the sum of all elements of all the possible subarrays of length n from the original array.For example, If the input is −const arr = [2, 6, 4]; const n = 2;Then the output should be −const output = [8, 10, 6];ExampleThe code for this will be −const arr = ... Read More

We are required to write a JavaScript function that takes in any number of arrays of numbers. Then the function should return an object that returns a frequency map indicating how many times each element has appeared checking in all the array.For example, If the arrays are −const a = [23, 45, 21], b = [45, 23], c = [21, 32], d = [23], e= [32], f=[50, 54];Then the output should be −const output = {    "21": 2,    "23": 3,    "32": 2,    "45": 2,    "52": 1,    "54": 1,    "23, 45": 2,    "23, ... Read More

Suppose we have an array of objects like this −const arr = [    {       duration: 10,       any: 'fields'    }, {       duration: 20,       any: 'other fields'    }, {       duration: 15,       any: 'some other fields'    } ];We are required to write a JavaScript function that takes in one such array and returns the summed result of the duration properties of all the objects.For the above array, the output should be 45.ExampleThe code for this will be −const arr = [ ... Read More

Suppose, we have an array of names like this −const arr = ["Simon", "Mike", "Jake", "Lara", "Susi", "Blake", "James"];We are required to write a JavaScript function that takes in one such array. The function should return an array of objects with two properties −letter -> the letter on which the names are groupednames -> an array of names that falls in that groupExampleThe code for this will be −const arr = ["Simon", "Mike", "Jake", "Lara", "Susi", "Blake", "James"]; const groupNames = arr => {    const map = arr.reduce((acc, val) => {       let char = val.charAt(0).toUpperCase();   ... Read More

We are required to write a JavaScript function that takes in an array that contains some false values. The function should remove all the null values from the array (if there are any) in place.For example: If the input array is −const arr = [12, 5, undefined, null, 0, false, null, 67, undefined, false, null];Then the output should be −const output = [12, 5, undefined, 0, false, 67, undefined, false];ExampleThe code for this will be −const arr = [12, 5, undefined, null, 0, false, null, 67, undefined, false, null]; const removeNullValues = arr => {    for(let i = 0; ... Read More