Angelfire

// {
//     prop: {
//         prop: {
//             prop: 3
//         }
//     }
// }

// {
//     prop: 3

Angelfire

class LinkedList {
    constructor() {
        this.head = null
    }

    addFirst(node) {
        if (this.head === null) {
            this.head = node
        } else {
            node.next = this.head

Angelfire

const Stack = require('./Stack');

class OperationManager {
    constructor() {
        this.operations = new Stack()
        this.undos = new Stack()
    }

    addOperation(operation) {
        this.operations.push(operation)

Angelfire

// Given an array of fruits in this format:

// [
//     { food: 'apple', type: 'fruit' }, 
//     { food: 'orange', type: 'fruit' }, 
//     { food: 'carrot', type: 'vegetable' }
// ]

// Let's turn it into an object with this format:
// { 

Angelfire

function removeDuplicates(arr) {
  return arr.filter((el, idx) => arr.indexOf(el) === idx)
}

function removeDuplicates(numbers) {
    return numbers.reduce((accumulator, currentValue) => {
        if(accumulator.indexOf(currentValue) === -1) {
            accumulator.push(currentValue)
        }

Angelfire

// By default, the reduce function will use the first value in the array as the accumulator if an accumulator is not provided.

// numbers is an array full of numbers
// let's find the largest and return it
// i.e. [2,3,5,1,4] => 5
function largest(numbers) {
    return numbers.reduce((accumulator, currentValue) => {
        return accumulator > currentValue ? accumulator : currentValue
    });
}

Angelfire

const MONTHS = [
    'JAN', 'FEB', 'MAR', 'APR', 'MAY', 'JUN',
    'JUL', 'AUG', 'SEP', 'OCT', 'NOV', 'DEC'
];

const events = [{ event: 'dance', month: 'MAR' },
 { event: 'farmers market', month: 'JUN' },
 { event: 'parade', month: 'JAN' }]

function sortByMonth(events) {

Angelfire

const students = [
    { id: 1, graduated: true, grade: 86 },
    { id: 2, graduated: false, grade: 96 },
    { id: 3, graduated: false, grade: 78 },
    { id: 4, graduated: true, grade: 96 },
];

function sortStudents(students) {
    return students.sort((a, b) => {
        if (a.graduated !== b.graduated) {

Angelfire

const Shape = require('./Shape');

function Circle(x, y, radius) {
    Shape.call(this, x, y);
    // store radius on this
    this.radius = radius
}

// Object.create is used to link our prototypes within the prototype chain.
// Now our Circle prototype inherits methods from the Shape Prototype! Any new circle will have a move method.

Angelfire

/* Within the function Celebrity, a method is used to fetch the celebrity's age. The second argument to fetchAge is a callback function. The callback function will receive age as an argument.
⚠️ Unfortunately, due to the function call-site, this will be re-defined to not refer to the celebrity. Running the tests without modifying the code will result in a TypeError.
Fix this.age to refer to the same this as the function Celebrity.
*/

const fetchAge = require('./fetchAge');

function Celebrity(name) {
    this.name = name;