We are required to write a JavaScript function that takes in two numbers, say m and n and returns two numbers whose sum is n and product is m. If there exist no such numbers, then our function should return falseLet’s write the code for this function −Exampleconst perfectNumbers = (sum, prod) => {    for(let i = 0; i < (sum / 2); i++){       if(i * (sum-i) !== prod){          continue;       };       return [i, (sum-i)];    };    return false; }; // 12 12 are not two distinct numbers console.log(perfectNumbers(24, 144)); console.log(perfectNumbers(14, 45)); console.log(perfectNumbers(21, 98));OutputFollowing is the output in the console −false [ 5, 9 ] [ 7, 14 ]

We are required to write a JavaScript function that takes in array of strings and delete every one of the two string that start with the same letter.For example, If the actual array is −const arr = ['Apple', 'Jack' , 'Army', 'Car', 'Jason'];Then, we have to keep only one string in the array, so one of the two strings starting with A should get deleted. In the same way, the logic follows for the letter J in the above array.Let’s write the code for this function −Exampleconst arr = ['Apple', 'Jack' , 'Army', 'Car', 'Jason']; const delelteSameLetterWord = arr => ... Read More

In this article, we will learn to convert an array with a null value to a string in Javascript. Handling arrays containing null, undefined, and falsy values in JavaScript is a frequent challenge. The default methods might not behave as expected when converting such arrays to strings, requiring custom solutions for meaningful string representations. Problem Statement Given an array containing null, undefined, empty strings, and other values, the task is to concatenate its elements into a single string while excluding the unwanted values. Following is our array, with some null and undefined values − Input ["Here", "is", null, "an", undefined, ... Read More

We are required to write a JavaScript function that takes in a negative integer and returns the sum of its digitsFor example −-234 --> -2 + 3 + 4 = 5 -54  --> -5 + 4 = -1Let’s write the code for this function −ExampleFollowing is the code −const num = -4345; const sumNum = num => {    return String(num).split("").reduce((acc, val, ind) => {       if(ind === 0){          return acc;       }       if(ind === 1){          acc -= +val;          return acc;       };       acc += +val;       return acc;    }, 0); }; console.log(sumNum(num));OutputFollowing is the output in the console −8

We are required to write a JavaScript function that takes in an array of numbers with duplicate entries and sums all the duplicate entries to one indexFor example −If the input array is −const input = [1, 3, 1, 3, 5, 7, 5, 4];Then the output should be −const output = [2, 6, 7, 10, 4];ExampleLet’s write the code −const input = [1, 3, 1, 3, 5, 7, 5, 3, 4]; const sumDuplicate = arr => {    const map = arr.reduce((acc, val) => {       if(acc.has(val)){          acc.set(val, acc.get(val) + 1);       }else{          return acc;       }, new Map()); }    return Array.from(map, el => el[0] * el[1]); }; console.log(sumDuplicate(input));OutputFollowing is the output in the console −[ 2, 9, 10, 7, 4 ]

We are required to write a JavaScript function that takes in a number and returns the difference of the sums of the digits at even place and the digits odd placeExampleLet’s write the code −const num = 345336; const evenOddDifference = (num, res = 0, ind = 0) => {    if(num){       if(ind % 2 === 0){          res += num % 10;       }else{          res -= num % 10;       };    };    return Math.abs(res); }; console.log(evenOddDifference(num));OutputFollowing is the output in the console −2

We have two arrays of objects like these −const blocks = [    { id: 1 },    { id: 2 },    { id: 3 },    { id: 4 }, ] const containers = [    { block: { id: 1 } },    { block: { id: 2 } },    { block: { id: 3 } }, ]We are required to write a function that checks each object of blocks array with the block key of each object of containers array and see if there exists any id in blocks array that is not present in ... Read More

We have an array of numbers like this −const arr = [-1, -2, -1, 0, -1, -2, -1, -2, -1, 0, 1, 0];Let’s say, we are required to write a JavaScript function that counts the consecutive groups of negative numbers in the array.Like here we have consecutive negatives from index 0 to 2 which forms one group and then from 4 to 8 forms the second groupSo, for this array, the function should return 2.ExampleLet’s write the code −const arr = [-1, -2, -1, 0, -1, -2, -1, -2, -1, 0, 1, 0]; const countNegativeGroup = arr => {   ... Read More

We are required to write a JavaScript function that computes the Factorial of a number n by making use of recursive approach.Here, we are finding the factorial recursion and creating a custom function recursiceFactorial() −const num = 9; const recursiceFactorial = (num, res = 1) => {    if(num){       return recursiceFactorial(num-1, res * num);    };    return res; };Now, we will call the function and pass the value to find recursion −console.log(recursiceFactorial(num)); console.log(recursiceFactorial(6)); console.log(recursiceFactorial(10));ExampleLet’s write the code for this function −const num = 9; const recursiceFactorial = (num, res = 1) => {    if(num){   ... Read More

Let’s say, we have an array of objects like this −data = [    {"Age":26, "Level":8},    {"Age":37, "Level":9},    {"Age":32, "Level":5},    {"Age":31, "Level":11},    {"Age":null, "Level":15},    {"Age":null, "Level":17},    {"Age":null, "Level":45} ];We are required to write a JavaScript function that calculates the average level for all the objects that have a truthy value for age propertyLet’s write the code for this function −ExampleFollowing is the code −data = [    {"Age":26, "Level":8},    {"Age":37, "Level":9},    {"Age":32, "Level":5},    {"Age":31, "Level":11},    {"Age":null, "Level":15},    {"Age":null, "Level":17},    {"Age":null, "Level":45} ]; const findAverage = arr => { ... Read More