ProblemWe are required to write a JavaScript function that takes in a 2-D binary array, arr, (an array that consists of only 0 or 1), as the first and the only argument.Our function should first flip the matrix horizontally, then invert it, and return the resulting matrix.To flip the matrix horizontally means that each row of the matrix is reversed. For example, flipping [1, 1, 0] horizontally results in [0, 1, 1].To invert a matrix means that each 0 is replaced by 1, and each 1 is replaced by 0. For example, inverting [0, 1, 1] results in [1, 0, ... Read More

Mountain SubsequenceWe call any (contiguous) subarray sub (of arr) a mountain if the following properties hold −sub.length >= 3There exists some 0 < i < sub.length - 1 such that sub[0] < sub[1] < ... sub[i-1] < sub[i] > B[i+1] > ... > sub[sub.length - 1]ProblemWe are required to write a JavaScript function that takes in an array of numbers, arr, as the first and the only argument.Our function is supposed to return the length of the greatest mountain subsequence present in the array arr, if there exists any, 0 otherwise.For example, if the input to the function isInputconst arr ... Read More

ProblemWe 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 numbers in the array are in the range [1, 13], limits inclusive, representing the 1-based index of playing cards.Our function should determine whether there exists a way to rearrange the cards into groups so that each group is size num, and consists of num consecutive cards.For example, if the input to the function isInputconst arr = [1, 4, 3, 2]; const num = 2;Outputconst output = 2;Output ExplanationBecause the cards can be ... Read More

Centrally Peaked ArrayWe call an array arr a centrally peaked array if the following properties hold −arr.length >= 3There exists some i with 0 < i < arr.length - 1 such thatarr[0] < arr[1] < ... arr[i-1] < arr[i]arr[i] > arr[i+1] > ... > arr[arr.length - 1]ProblemWe are required to write a JavaScript function that takes in an array of numbers, arr, as the first and the only argument.The input array is a centrally peaked array. Our function is supposed to return the peak index of this centrally peaked array.For example, if the input to the function isInputconst arr = ... Read More

ProblemWe are required to write a JavaScript function that takes in a balanced square bracket string, str, as the first and the only argument.Our function should compute and return the score of the string based on the following rule −[] has score 1AB has a score A + B, where A and B are balanced bracket strings.[A] has score 2 * A, where A is a balanced bracket string.For example, if the input to the function isInputconst str = '[][]';Outputconst output = 2;ExampleFollowing is the code −const findScore = (str = '') => {    const arr = []   ... Read More

ProblemWe are required to write a JavaScript function that takes in an array of numbers, arr, as the first and the only argument.Let us consider the following situation:A shopkeeper sells a single commodity which costs exactly ₹5. Some customers are standing in a queue and will purchase exactly one unit of this commodity each. The customers can provide the shopkeeper with a note of ₹5, ₹10 or ₹20. Considering that the shopkeeper has no money in the beginning and the array represents the notes given by the customers standing in the queue.Our function should determine whether or not the shopkeeper ... Read More

ProblemWe are required to write a JavaScript function that takes in two arrays of numbers, arr1 and arr2, of the same length.Our function should shuffle the elements of the first array, arr1, such that its maximum number of elements are greater than corresponding elements of the array arr2. The function should then return the shuffled array.For example, if the input to the function isInputconst arr1 = [3, 5, 12, 19]; const arr2 = [2, 9, 3, 12];Outputconst output = [3, 12, 5, 19];Output ExplanationBefore shuffling arr1, it had 3 corresponding elements greater than that of arr2, but in the shuffled ... Read More

Fibonacci Sequence:A sequence X_1, X_2, ..., X_n is fibonacci if:n >= 3X_i + X_{i+1} = X_{i+2} for all i + 2 {    const map = arr.reduce((acc, num, index) => {       acc[num] = index       return acc    }, {})    const memo = arr.map(() => arr.map(() => 0))    let max = 0    for(let i = 0; i < arr.length; i++) {       for(let j = i + 1; j < arr.length; j++) {          const a = arr[i]          const b = arr[j]          const index = map[b - a]          if(index < i) {             memo[i][j] = memo[index][i] + 1          }          max = Math.max(max, memo[i][j])       }    }    return max > 0 ? max + 2 : 0 }; console.log(longestFibonacci(arr));Output5

ProblemWe are required to write a JavaScript function that takes in the head of a linked list as the first and the only argument.Our function should return the value stored in the middlemost node of the list. And if there are two middlemost nodes, we should return the second one of them.For example, if the list is like this:Input[4, 6, 8, 9, 1]Outputconst output = 8;Following is the code:Exampleclass Node {    constructor(data) {       this.data = data;       this.next = null;    }; }; class LinkedList {    constructor() {       this.head = ... Read More

ProblemWe are required to write a JavaScript function that takes in two arrays of numbers, arr1 and arr2, as the first and the second argument.The sum of elements in arr1 and arr2 are different. Our function should pick one element from the first array and push it in the second array and pick one element from the second array and push it in the first array such that the sum of the elements of both the arrays become equal. We should return an array of these two elements.For example, if the input to the function isInputconst arr1 = [1, 2, ... Read More