Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Palindrome Sequence:A string sequence is known as palindrome sequence if it reads the same from front and the back. For instance, 'aba', 'madam, 'did' are all valid palindrome sequences.We are required to write a JavaScript function that takes in a string as the first and the only argument. The string taken as input is guaranteed to consist of only 'a', 'b', 'c' and 'd'. Our function should count and return the number of all contiguous or noncontiguous palindrome subsequences that appear in the string.For example −If the input string is −const str = 'bccb';Then the output should be −const output ... Read More
We are required to write a JavaScript function that takes in an array of numbers, arr, as the first argument and a number, num, as the second argument.The function should determine whether there exists a way of distributing the elements of the array arr into num groups such that all the groups have equal sum. If there exists any such way, our function should return true, false otherwise.For example −If the input array and the number are −const arr = [4, 6, 3, 3, 7, 4, 1]; const num = 4;Then the output should be −const output = true;because the ... Read More
For the purpose of this question, we define a sentence as a string that contains English alphabets and punctuations and a word is a substring of that sentence joined together by whitespaces.We are required to write a JavaScript function that takes in a sentence string, str, as the first argument and a number, num, as the second argument. The function should first count the frequency of each word in the sentence and then return an array of length num containing num most frequent words placed according to decreasing frequencies.For example −If the input sentence and the number is −const str ... Read More
We are required to write a JavaScript function that takes in an array of string words as the first argument. The second argument to the function will be a string containing all 26 English lowercase alphabets but in some random scrambled order.The task of our function is to check whether the words in the array are placed lexicographically correctly according to the order specified by the second argument. If it is so, we should return true, false otherwise.For example −If the input array of words and the order is −const arr = ['this', 'is', 'something', 'mad']; const order = 'hdetljnopqabcuvwxfgirsykmz';Then ... Read More
We are required to write a JavaScript function that takes in a number as the first and the only argument. The function should then square every digit of the number, append them and yield the new number.For example −If the input number is −const num = 12349;Then the output should be −const output = 1491681;because '1' + '4' + '9' + '16' + '81' = 1491681ExampleThe code for this will be − Live Democonst num = 12349; const squareEvery = (num = 1) => { let res = '' const numStr = String(num); const numArr = numStr.split(''); ... Read More
Suppose we have a keyword, which instead of the traditional qwerty type key mapping, maps keys simply according to the english alphabetic order i.e., abcde...Before we dive into the problem, we have to make the following two assumptions −Currently our fingertip is placed at index 0, i.e., the key 'aThe time taken to move from one key to some other is the absolute difference of their index, for example the time taken to move from 'a' to 'k' will be |0 - 10| = 10We are required to write a JavaScript function that takes in a string of english lowercase ... Read More
Anagram arrays:One array is an anagram of another if we can randomise the elements of that array to achieve the other array.For example −[1, 2, 3] and [2, 1, 3] are anagrams of each other.Suppose, we have two arrays, arr1 and arr2 which are anagrams of each other.We are required to write a JavaScript function that takes in these two arrays and returns a new mapping array of the same length as arr1 and arr2. The mapping array should contain the index of elements of the arr1 array as they are present in the arr2 array.For example −If the two ... Read More
We are required to write a JavaScript function that takes in three arrays of integers all sorted in an increasing order. The function should then construct and return an array that contains only those elements that present in all three arrays.For example −If the input arrays are −const arr1 = [4, 7, 8, 11, 13, 15, 17]; const arr2 = [1, 3, 4, 13, 18]; const arr3 = [2, 4, 7, 8, 9, 10, 13];Then the output should be −const output = [4, 13];ExampleThe code for this will be − Live Democonst arr1 = [4, 7, 8, 11, 13, 15, 17]; ... Read More
We are required to write a JavaScript function that takes in four arguments. The four arguments will all be arrays of exactly two numbers representing the coordinates of four vertices of a quadrilateral or any figure (closed or unclosed) on a plane.The task of our function is to determine whether or not the four vertices form a square.If they do form a square, we should return true, false otherwise.For example −If the input coordinates are −const c1 = [1, 0]; const c2 = [-1, 0]; const c3 = [0, 1]; const c4 = [0, -1];Then the output should be −const ... Read More
We are required to write a JavaScript function that takes in a binary array (an array that consists of 0 or 1 only) as the only argument.The function should find the length of that consecutive subarray of the array that consists of only 1 and return it.For example −If the input array is −const arr = [1, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 1];Then the output should be −const output = 4;We will use the sliding window algorithm to capture the largest window (largest in size) that consists of only 1.ExampleThe code for this ... Read More