4skinSkywalker

function countdown(num) {

    console.log(num)

    // Base Case with return inside
    if (num === 0)
        return

    // recursive call with a different input
    countdown(num - 1)

4skinSkywalker

function egg() {
  chicken()
}

function chicken() {
  egg()
}

chicken() // your PC explodes and a new universe is born

4skinSkywalker

function maxKAdjacentSum(array, k) {
    if (array.length < k)
        return null
    
    let runningSum = 0
    for (let i = 0; i < k; i++)
        runningSum += array[i]

    let highestSum = runningSum
    for (let j = 0; j < array.length - k; j++) {

4skinSkywalker

function countUnique(iterable) {
    if (iterable.length < 1)
        return 0

    let i = 0
    let j = 1

    let count = 1
    for (; j < iterable.length; j++) {
        if (iterable[i] !== iterable[j]) {

4skinSkywalker

function sumZero(array) {
    let left = 0
    let right = array.length - 1

    while (left < right) {
        let sum = array[left] + array[right]

        if (sum === 0)
            return true

4skinSkywalker

function same(a1, a2) {
    if (a1.length !== a2.length)
        return false

    let fc1 = frequencyCounter(a1)
    let fc2 = frequencyCounter(a2)

    for (let key in fc1)
        if (!key in fc2 || fc1[key] !== fc2[key])
            return false

4skinSkywalker

function anagrams(s1, s2) {
    if (s1.length !== s2.length)
        return false

    let fc1 = frequencyCounter(s1)
    let fc2 = frequencyCounter(s2)

    for (let key in fc1)
        if (!key in fc2 || fc1[key] !== fc2[key])
            return false

4skinSkywalker

function frequencyCounter(iterable) {
  let fc = {}

  for (let item of iterable)
    fc[item] = fc[item] + 1 || 1

  return fc
}

4skinSkywalker

let string = "hello world"

let frequencyCounter = {
  " ": 1
  d: 1
  e: 1
  h: 1
  l: 3
  o: 2
  r: 1

4skinSkywalker

class Percolation {
  constructor(UnionFind, SquareGrid) {}

  init(gridSize) {
    // init union-find
    this.uf = new UnionFind(gridSize ** 2 + 2);

    // init top virtual node
    let top = 0;
    for (let i = 1; i <= gridSize; i++) {