JsnGmz

import java.util.Collection;
import java.util.Comparator;
import java.util.EnumMap;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;

JsnGmz

import java.util.ArrayDeque;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Deque;
import java.util.PriorityQueue;
import java.util.Queue;

public class JavaQueues {

JsnGmz

import java.util.Arrays;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Set;
import java.util.SortedSet;
import java.util.TreeSet;

public class JavaSets {
    public static void main(final String[] args) {

JsnGmz

import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;

public class JavaLists {
    public static void main(String[] args) {
        
        ////////////////////////////

JsnGmz

class Queue {

 constructor() {
  this.queue = [];
 }
 
// Allows us add items to the back of the array.
 enqueue(item) {
  this.queue.push(item);
 }

JsnGmz

class Queue {

 constructor() {
  this.queue = [];
  this.stack = [];
 }
 
dequeue() {
  if (this.stack.length === 0) {
   while (this.queue.length > 0) {

JsnGmz

class Stack {

 constructor() {
  this.stack = [];
 }
 
push(item) {
  this.stack.push(item);
 }
 

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class Node {
  constructor(data, next) {
    this.data = data;
    this.next = null;
  }
}

const linkedList = new Node(5);
linkedList.next = new Node(10);
linkedList.next.next = new Node(15);

JsnGmz

class Node {
  constructor(data, prev = null, next = null) {
    this.data = data;
    this.prev = prev;
    this.next = next;
  }
}
const doubleLinkedList = new Node(0);
const secondItem = doubleLinkedList.next = new Node(1, doubleLinkedList);
const thirdItem = secondItem.next = new Node(2, secondItem);

JsnGmz

class Node {
  constructor(data) {
    this.data = data;
    this.left = null;
    this.right = null;
  }
}
class Tree {
  constructor(data) {
    const node = new Node(data);