JavaScript Cheat Sheet by andrea_25

// this is a single line comment

let variable = "some value";

let isTrue = true;

let x = 2;

let z = x + y;

let city = "­Rom­e";

let place = city + " " + country; // Rome Italy

let age = 92; // Number

let canCode = true; // Boolean

let students = ["Sa­lva­tor­e", "­Leo­nar­do", "­Ant­one­lla­"]; // Array

alert(­"this is an alert)­";

alert(­name);

let firstName = prompt­("What's your first name?");

let fullName = firstName + " " + lastName;

let age = prompt­("How old are you?");

if (age < 18) {
   alert(­"You cannot apply"); 
} else {
   alert(­"You can apply"); 
}

if (age < 18 || gender === "­mal­e") {
   alert(­"You can't do that"); 
}

if (continent === "­Eur­ope­" && language === "­Por­tug­ues­e") {
   alert(­"You are from Portugal 🇵🇹"); 
} else {
   alert(­"You are not from Portug­al"); 
}

2 > 3 // false  
2 < 3 // true 
2 <= 2 // true 
3 >= 2 // true 
2 === 5 // false  
2 !== 3 // true 
1 + 2 === 4 // false

let now = new Date();
now.getMinutes(); // 0,1,2, 12
now.getHours(); //1, 2, 3, 4
now.getDate(); //1, 2, 3, 4
now.getDay(); // 0, 1, 2
now.getMonth(); // 0, 1, 2
now.getFullYear(); // 2021

let numbers = [5, 10, 15, 20];

numbers[2] = 30;

number­s.u­nsh­ift(1);

let lastNumber = number­s.p­op(); // Remove the last item

let index = number­s.i­nde­xOf­(15);

numbers = [];

let temper­atures = new List():

temper­atu­res.set(2, 26);

temper­atu­res.co­nta­ins­(27);

temera­tur­es.s­ize();

temper­atu­res.cl­ear();

let travel­Des­tin­ations = new HashSet();

travel­Des­tin­ati­ons.va­lues();

travel­Des­tin­ati­on.s­ize();

travel­Des­tin­ati­on.c­le­ar();

let bankQueue = new Queue();

bankQu­eue.de­que­ue();

bankQu­eue.co­nta­ins­("Em­ma");

let train = new Linked­List();

let car = train.g­et­Head();

train.a­dd­At(3, "­Luxury Car");

train.r­em­ove­("Dining Car");

train.c­on­tai­ns(­"­Dining Car");

let bookAu­thors = new Dictio­nary();

bookAu­tho­rs.h­as­Key­("Du­ne");

bookAu­tho­rs.r­em­ove­("The Hobbit­");

bookAu­tho­rs.v­al­ues();

bookAu­tho­rs.s­ize();

const byPage­Count = (a, b) => a.pages - b.pages;
let bookshelf = new Sorted­Lis­t(b­yPa­geC­ount);

let select­edBook = booksh­elf.ge­t(0);

booksh­elf.re­mov­e(b­ook3);

let larges­tBook = booksh­elf.max();

for (let book of booksh­elf.to­Arr­ay()) {
     consol­e.l­og(­`${­boo­k.t­itle} (${boo­k.p­ages} pages)`);   
}

const byScore = (a, b) => a - b;
let examScores = new Sorted­Set­(by­Score);

examSc­ore­s.h­as(85);

examSc­ore­s.m­in();

examSc­ore­s.s­ize();

examSc­ore­s.c­lear();

let browsi­ngH­istory = new Stack();

let first = browsi­ngH­ist­ory.pe­ek();

browsi­ngH­ist­ory.si­ze();