Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
The power of the string is the maximum length of a non−empty substring that contains only one unique character.We are required to write a JavaScript function that takes in a string and returns its power.For example −const str = "abbcccddddeeeeedcba"Then the output should be 5, because the substring "eeeee" is of length 5 with the character 'e' only.ExampleThe code for this will be −const str = "abbcccddddeeeeedcba" const maxPower = (str = '') => { let power = 1 const sz = str.length - 1 for(let i = 0; i < sz; ++i) { ... Read More
We are required to write a JavaScript function that takes in an array of arrays. Each subarray will contain exactly two items, representing the x and y coordinates respectively.Our function should check whether or not the coordinates specified by these subarrays form a straight line.For example −[[4, 5], [5, 6]] should return true.The array is guaranteed to contain at least two subarrays.ExampleThe code for this will be −const coordinates = [ [4, 5], [5, 6] ]; const checkStraightLine = (coordinates = []) => { if(coordinates.length === 0) return false; let x1 = coordinates[0][0]; let y1 = coordinates[0][1]; let slope1 = null; for(let i=1;i
Like the base−2 representation (binary), where we repeatedly divide the base 10 (decimal) numbers by 2, in the base 7 system we will repeatedly divide the number by 7 to find the binary representation.We are required to write a JavaScript function that takes in any number and finds its base 7 representation.For example −base7(100) = 202ExampleThe code for this will be −const num = 100; const base7 = (num = 0) => { let sign = num < 0 && '−' || ''; num = num * (sign + 1); let result = ''; while (num) { result = num % 7 + result; num = num / 7 ^ 0; }; return sign + result || "0"; }; console.log(base7(num));OutputAnd the output in the console will be −202
Suppose, we have an array of objects like this −const arr = [ { col1: ["a", "b"], col2: ["c", "d"] }, { col1: ["e", "f"], col2: ["g", "h"] } ];We are required to write a JavaScript function that takes in one such array and returns the following output.const output = [ { col1: "b", col2: "d" }, { col1: "f", col2: "h" } ];Basically, we want to convert ... Read More
We are required to write a JavaScript function that takes in two strings as arguments. The function should then check the two strings for common characters and prepare a new string of those characters.Lastly, the function should return that string.The code for this will be −Exampleconst str1 = "IloveLinux"; const str2 = "weloveNodejs"; const findCommon = (str1 = '', str2 = '') => { const common = Object.create(null); let i, j, part; for (i = 0; i < str1.length - 1; i++) { for (j = i + 1; j
Suppose we have two arrays of objects like these −const arr1 = [{id:'1', name:'A'}, {id:'2', name:'B'}, {id:'3', name:'C'}, {id:'4', name:'D'}]; const arr2 = [{id:'1', name:'A', state:'healthy'}, {id:'3', name:'C', state:'healthy'}];We are required to write a JavaScript function that takes in two such arrays. Our function should return a new filtered version of the first array (arr1 in this case) that contains only those objects with a name property that are not contained in the second array (arr2 in this case) with the same name property.Therefore, the output, in this case, should look like −const output = [{id:'2', name:'B'}, {id:'4', name:'D'}];ExampleThe code ... Read More
Suppose, we have an array of objects like this −const arr = [{ name : 'Client 1', total: 900, value: 12000 }, { name : 'Client 2', total: 10, value: 800 }, { name : 'Client 3', total: 5, value : 0 }];We are required to write a JavaScript function that takes in one such array and extracts a separate array for each object property.Therefore, one array for the name property of each object, one for total and one for value. If there existed more properties, we would have separated more ... Read More
We are required to illustrate the correct way to check whether a particular key exists in an object or not. Before moving on to the correct way let's first examine an incorrect way and see how actually its incorrect.Way 1: Checking for undefined value (incorrect way)Due to the volatile nature of JavaScript, we might want to check for the existence of key in an object like this −const obj = { name: 'Rahul' };if(!obj['fName']){}orif(obj['fName'] === undefined){}These both are incorrect ways. Why?Because in this case there happens to be no 'fName' key, but suppose there existed a 'fName' which was deliberately ... Read More
We are required to write a JavaScript function that takes in an array of numbers. Our function should return true if the difference between all adjacent elements is the same positive number, false otherwise.ExampleThe code for this will be −const arr = [4, 7, 10, 13, 16, 19, 22]; const growingMarginally = arr => { if(arr.length
const sort = ["this", "is", "my", "custom", "order"]; const myObjects = [ {"id":1, "content":"is"}, {"id":2, "content":"my"}, {"id":3, "content":"this"}, {"id":4, "content":"custom"}, {"id":5, "content":"order"} ];We are required to write a JavaScript function that takes in two such arrays and sorts the second array of objects on the basis of the first array so that the content property of objects are matched with the strings of the first array.Therefore, for the above arrays the output should look like −const output = [ {"id":3, "content":"this"}, {"id":1, "content":"is"}, {"id":2, "content":"my"}, {"id":4, "content":"custom"}, {"id":5, "content":"order"} ];ExampleThe ... Read More