Playground - Crea una cola de emails

🛡️🛡️Escudo anti-spoilers🛡️🛡️

Mi solución al reto:

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    let newMail = new Mail(from, to, body, subject)
    if (this.length == 0) {
      this.first = newMail
      this.last = newMail
    } else {
      this.last.next = newMail
      this.last = newMail
    }
    this.length++
  }

  dequeue() {
    let r = this.first;
    if (this.first === this.last)
      this.last = null;
    this.first = this.first.next;
    this.length--
    delete r.next
    return r;
  }

  peek() {
    if (!this.first) return null
    return {
      from: this.first.from,
      to: this.first.to,
      body: this.first.body,
      subject: this.first.subject
    }
  }

  size() {
    return this.length
  }
}

🛡️🛡️🛡️Escudo anti spoilers🛡️🛡️🛡️

Crea una cola de emails

Con ansias de que se venga el día 30 y tambien 30 días de Python 😍

Nunca pares de aprender 🦾

import { Node } from "./node";

export class Playlist {
  constructor() {
    this.top = null;
    this.bottom = null;
    this.length = 0;
  }

  addSong(song) {
    const newSong = new Node(song);
    if (!this.top) {
      this.top = newSong
      this.bottom = newSong
      console.log(this);
    }
    else {
      newSong.next = this.top
      this.top = newSong
    }
    this.length++;
    return this
  }

  playSong() {
    if (!this.top) {
      throw new Error("No hay canciones en la playlist")
    }
    if (this.top == this.bottom) {
      this.bottom = null
    }
    const playedSong = this.top.value
    this.top = this.top.next
    this.length--;
    return playedSong
  }

  getPlaylist() {
    const playList = []
    if (!this.top) {
      return []
    }
    if (this.top) {
      playList.push(this.top.value)
      console.log(this.top.value)
      let currentSong = this.top
      while (currentSong.next) {
        playList.push(currentSong.next.value)
        currentSong = currentSong.next
      }
    }
    return playList
  }
}

Mi solución al problema.
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mail.js

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }
}

exercise.js

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newNode = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newNode;
      this.last = newNode;
    } else {
      this.last.next = newNode;
      this.last = newNode;
    }
    this.length++;
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("La queue está vacía");
    }

    const removedNode = this.first;
    if (this.first === this.last) {
      this.last = null;
    }

    this.first = this.first.next;
    this.length--;

    return {
      from: removedNode.from,
      to: removedNode.to,
      body: removedNode.body,
      subject: removedNode.subject,
    };
  }

  peek() {
    if (this.length === 0) {
      throw new Error("La queue está vacía");
    }

    let currentNode = this.first;
    currentNode.next = null;

    return currentNode;
  }

  size() {
    return this.length;
  }
}

Creo que hay un error por parte de la eliminación del email ya que al desesctructurar el email mas viejo para quitar la clave que contiene al siguiente nodo/email retorna error, y funciona si simplemente se retorna el email mas antiguo junto con la clave de el email siguiente
Mi solución al reto:
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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newNode = new Mail(from, to, body, subject)
    if (this.length === 0) {
    this.last = newNode
    this.first = newNode
    }
    this.last.next = newNode
    this.last = newNode
    return this.length++
  }

  dequeue() {
    if (!this.first) {
      throw new Error('No hay elementos en la cola')
    }
    if (this.first === this.last) {
      this.last = null
    }
    const deleteEmail = this.first
    this.first = this.first.next
    this.length--
    return deleteEmail
  }

  peek() {
    const oldEmail = this.first
    delete oldEmail.next
    return oldEmail
  }

  size() {
    return this.length
  }
}

Hola dejo mi solución:

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Exercise.js

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newMail = new Mail(from, to, body, subject);
    if (this.isEmpty()) {
      this.first = newMail;
    } else {
      this.last.next = newMail;
    }
    this.last = newMail;
    this.length++;
  }

  dequeue() {
    if (this.isEmpty()) {
      throw new Error("La cola está vacía");
    }
    const removedMail = this.first;
    if (this.length === 1) {
      this.first = null;
      this.last = null;
    } else {
      this.first = removedMail.next;
    }
    removedMail.next = null;
    this.length--;
    return removedMail;
  }

  peek() {
    if (this.isEmpty()) {
      throw new Error("La cola está vacía");
    }
    return this.first;
  }

  isEmpty() {
    return this.length === 0;
  }

  size() {
    return this.length;
  }
}

💚Mi Solución💚

🛡️Escudo Anti-Spoilers🛡️

##👾Código👾

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newMail = new Mail(from, to, body, subject)

    if (this.length == 0) {
      this.first = newMail
      this.last = newMail
    } else {
      this.last.next = newMail
      this.last = newMail
    }

    this.length++
  }

  dequeue() {
    if (this.length == 0)
      throw new Error("No hay más mails")

    const mail = this.first
    this.first = this.first.next

    if (this.length-- == 1)
      this.last = null

    return mail
  }

  peek() {
    return this.first
  }

  size() {
    return this.length
  }
}

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exercise.js

class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newMail = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newMail;
      this.last = newMail;
    } else {
      this.last.next = newMail;
      this.last = newMail;
    }
    this.length++;
  }

  dequeue() {
    if (this.length === 0) throw new Error("La queue está vacía");
    if (this.first === this.last) this.last = null;

    const deletedEmail = this.first;
    this.first = this.first.next;
    this.length--;

    return deletedEmail;
  }

  peek() {
    return this.first;
  }

  size() {
    return this.length;
  }
}

Mi solucion:
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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    // Tu código aquí 👈🏻
    const newMail = new Mail(from, to, body, subject)
    // if (!this.first) Alternativa
    if (this.length === 0) {
      this.first = newMail;
      this.last = newMail;
    } else {
      this.last.next = newMail;
      this.last = newMail;
    }
    this.length++;
  }

  dequeue() {
    // Tu código aquí 👈🏻
    if (this.length === 0)
      throw new Error('No hay email a revisar');
    const { from, to, body, subject } = this.first;
    if (this.first === this.last)
      this.last = null;
    this.first = this.first.next;
    this.length--;
    return { from, to, body, subject };
  }

  peek() {
    // Tu código aquí 👈🏻
    if (this.length === 0)
      throw new Error('No hay email');
    return this.first;
  }

  size() {
    // Tu código aquí 👈🏻
    return this.length;
  }
}

Solución

class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    // Tu código aquí 👈🏻
    const newMail = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newMail;
      this.last = newMail;
    } else {
      this.last.next = newMail;
      this.last = newMail;
    }

    this.length++;
    return this;
  }

  dequeue() {
    // Tu código aquí 👈🏻

    const deletedMail = {
      from: this.first.from,
      to: this.first.to,
      body: this.first.body,
      subject: this.first.subject,
    };

    if (this.first === this.last) {
      this.first = null;
      this.last = null;
    } else {
      this.first = this.first.next;
    }

    this.length--;

    return deletedMail;
  }

  peek() {
    // Tu código aquí 👈🏻
    return this.first ? this.first : null;
  }

  size() {
    // Tu código aquí 👈🏻
    return this.length ? this.length : "Empty mailbox";
  }
}

🛡️🛡️Escudo anti-spoilers🛡️🛡️

Mi solución al reto

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }

  json() {
    let { from, to, body, subject } = this;
    return { from, to, body, subject };
  }
}

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newMail = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newMail;
      this.last = newMail;
    } else {
      this.last.next = newMail;
      this.last = newMail;
    }
    this.length++;
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("La queue está vacía");
    }

    const removedMail = this.first;
    if (this.first === this.last) {
      this.last = null;
    }

    this.first = this.first.next;
    this.length--;
    return removedMail.json();
  }

  peek() {
    return this.first.json();
  }

  size() {
    return this.length;
  }
}

Aquí mi solución:
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exercise.js

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newNode = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newNode;
      this.last = newNode;
    } else {
      this.last.next = newNode;
      this.last = newNode;
    }
    this.length++;
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("No hay correos en cola")
    }

    let { from, to, body, subject } = this.first;
    let removedNode = { from, to, body, subject };
    if (this.first === this.last) {
      this.last = null;
    }

    // Reasignamos los valores
    this.first = this.first.next;
    // y reducimos la longitud
    this.length--;

    // Se retorna el valor del nodo removido
    return removedNode;
  }

  peek() {
    if (this.length === 0) {
      throw new Error("No hay correos en cola")
    }

    let { from, to, body, subject } = this.first;
    let firstNode = { from, to, body, subject };

    return firstNode;
  }

  size() {
    return this.length;
  }
}

MI SOLUCION 💪
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class Mail

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }
}

class Queue

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newMail = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newMail;
      this.last = newMail;
    } else {
      this.last.next = newMail;
      this.last = newMail;
    }
    this.length++;
  }

  dequeue() {
    if (this.length === 0) throw new Error("Los mails están vacíos");
    const removedMail = {
      from: this.first.from,
      to: this.first.to,
      body: this.first.body,
      subject: this.first.subject
    };
    if (this.first === this.last) this.last = null;
    this.first = this.first.next;
    this.length--;
    return removedMail;
  }

  peek() {
    return {
      from: this.first.from,
      to: this.first.to,
      body: this.first.body,
      subject: this.first.subject
    };
  }

  size() {
    return this.length;
  }
}

mail.js

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }
  get() {
    return {from: this.from, to: this.to, body: this.body, subject: this.subject}
  }
}

exercise.js

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const node = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = node;
      this.last = node;
    } else {
      this.last.next = node;
      this.last = node;
    }
    this.length++;
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("La cola está vacía");
    }
    const node = this.first;
    if (this.first === this.last) {
      this.last = null;
    }
    this.first = this.first.next;
    this.length--;
    return node.get();
  }

  peek() {
    if (this.length === 0) {
      throw new Error("La cola está vacía");
    }
    return this.first.get();
  }

  size() {
    return this.length;
  }
}

estoy muy decepcionado con este ejercicio, porque el enunciado no corresponde con las pruebas unitarias, tuve que ver la solución para verificar, por favor, revisen para hacer los cambios correspondientes

Mi solución:
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mail.js

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }
}

exercise.js

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newEmail = new Mail(from, to, body, subject)
    if (this.length === 0) {
      this.first = newEmail
      this.last = newEmail
    } else {
      this.last.next = newEmail
      this.last = newEmail
    }
    this.length++
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("La lista de correos está vacía")
    }
    const {next, ...removedEmail} = this.first
    if (this.first === this.last) {
      this.last = null
    }
    this.first = this.first.next
    this.length--
    return removedEmail
  }

  peek() {
    const { next, ...firstEmail } = this.first
    return firstEmail
  }

  size() {
    return this.length
  }
}

Mi humilde solucion
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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newEmail = new Mail(from, to, body, subject)
    if (!this.length) {
      this.first = newEmail
      this.last = newEmail
    } else {
      this.last.next = newEmail
      this.last = newEmail
    }
    this.length++
  }

  dequeue() {
    if (!this.length) {
      throw new Error('La queue esta vacia')
    }
    let removedMail = this.first
    if (this.first === this.last) {
      this.last = null
    }
    this.first = this.first.next
    this.length--
    const { from, to, body, subject } = removedMail
    return { from, to, body, subject }
  }

  peek() {
    if (!this.first) return null
    const { from, to, body, subject } = this.first
    return { from, to, body, subject }
  }

  size() {
    return this.length
  }
}

Solución… 😄
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exercise.js:

import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    let newMail = new Mail(from, to, body, subject);

    if (!this.first) {
      this.first = newMail;
      this.last = newMail;
    } else { 
      this.last.next = newMail;
      this.last = newMail;
    }

    this.length++;
  }

  dequeue() {
    if (!this.first) { 
      throw new Error("No hay correos por revisar");
    }

    let removedMail = this.first;

    if (this.first === this.last) { 
      this.last = null;
    }

    this.first = this.first.next;
    this.length--;
    return removedMail.toObject();
  }

  peek() {
    if (!this.first) { 
      return null;
    }

    return this.first.toObject();
  }

  size() {
    return this.length;
  }
}

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mail.js:

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }

  toObject() { 
    return {
      from: this.from,
      to: this.to,
      body: this.body,
      subject: this.subject
    }
  }
}

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newMail = new Mail(from, to, body, subject);
    if (!this.first) {
      this.first = newMail;
      this.last = newMail;
    } else {
      this.last.next = newMail;
      this.last = newMail;
    }
    this.length++;
  }

  dequeue() {
    if (!this.first) {
      throw new Error("No hay elementos en la Queue");
    }
    const removedMail = this.first;
    if (this.first === this.last) {
      this.last = null;
    }
    this.first = removedMail.next;
    this.length--;
    removedMail.next = null;
    return {
      from: removedMail.from,
      to: removedMail.to,
      body: removedMail.body,
      subject: removedMail.subject,
    };
  }

  peek() {
    if (!this.first) {
      return null;
    }
    return {
      from: this.first.from,
      to: this.first.to,
      body: this.first.body,
      subject: this.first.subject,
    };
  }

  size() {
    return this.length;
  }
}

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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.items = [];
  }

  enqueue(from, to, body, subject) {
    const email = new Mail(from, to, body, subject);
    this.items.push(email);
  }

  dequeue() {
    if (this.isEmpty()) {
      throw new Error("No hay elementos en la Queue");
    }
    return this.items.shift().getData();
  }

  peek() {
    if (this.isEmpty()) {
      return null;
    }
    return this.items[0].getData();
  }

  size() {
    return this.items.length;
  }

  isEmpty() {
    return this.size() === 0;
  }
}

export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.timestamp = new Date().getTime();
  }

  getData() {
    return {
      from: this.from,
      to: this.to,
      body: this.body,
      subject: this.subject,
    };
  }
}

Mi solucion
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class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }
}

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    // Tu código aquí 👈🏻
    const newNode = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newNode;
      this.last = newNode;
    } else {
      this.last.next = newNode;
      this.last = newNode;
    }
    this.length++;
  }

  dequeue() {
    // Tu código aquí 👈🏻
    if (this.length === 0) {
      throw new Error("La queue está vacía");
    }

    const removedNode = this.first;
    if (this.first === this.last) {
      this.last = null;
    }

    this.first = this.first.next;
    this.length--;

    return {
      from: removedNode.from,
      to: removedNode.to,
      body: removedNode.body,
      subject: removedNode.subject
    };
  }

  peek() {
    // Tu código aquí 👈🏻
    return {
      from: this.first.from,
      to: this.first.to,
      body: this.first.body,
      subject: this.first.subject
    };
  }

  size() {
    // Tu código aquí 👈🏻
    return this.length;
  }
}

Mi solución:
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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newEmail = new Mail(from, to, body, subject);

    if (this.length === 0) {
      this.first = newEmail;
      this.last = newEmail;
    } else {
      this.last.next = newEmail;
      this.last = newEmail;
    }
    this.length++;    
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("La queue está vacía");
    }
    const removedMail = this.first;
    if (this.first === this.last) {
      this.last = null;
    }

    this.first = this.first.next;
    this.length--;

    const {from, to, body, subject } = removedMail;
    return { from, to, body, subject };
  }

  peek() {
    const { from, to, body, subject } = this.first;
    return { from, to, body, subject };
  }

  size() {
    return this.length;
  }
}

Mi solución:
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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const newNode = new Mail(from, to, body, subject);
    if (this.length === 0) {
      this.first = newNode;
      this.last = newNode;
    } else {
      this.last.next = newNode;
      this.last = newNode;
    }
    this.length++;
    return this;
  }

  dequeue() {
    if (this.length === 0) {
      throw new Error("La queue está vacía");
    }

    const removedNode = this.first;

    if (this.first === this.last) {
      this.last = null;
    }

    this.first = this.first.next;
    
    this.length--;

    return {
      "from": removedNode.from,
      "to": removedNode.to,
      "body": removedNode.body,
      "subject": removedNode.subject,
    };
  }

  peek() {
    return this.first;
  }

  size() {
    return this.length;
  }
}

Pos mi aporte sobre el problema 😄. Camino anti spoiler basado en puntitos:

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import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
    const email = new Mail(from, to, body, subject)

    if (this.last) this.last.next = email
    this.last = email
    if (!this.first) this.first = email

    this.length++
  }

  dequeue() {
    const emailRemoved = this.first
    this.first = this.first.next
    this.length--
    return emailRemoved
  }

  peek() {
    return this.first
  }

  size() {
    return this.length
  }
}

**Hola dejo mi codigo con explicaciones de cada operador, explicado con detalles, ya que los uso para repasar conseptos basico de codigo **
Mi solucion es :
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.
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//mail.js
export class Mail {
  constructor(from, to, body, subject) {
    this.from = from;
    this.to = to;
    this.body = body;
    this.subject = subject;
    this.next = null;
  }
}

.

//exercise.js
import { Mail } from "./mail";

export class Queue {
  constructor() {
    this.first = null;
    this.last = null;
    this.length = 0;
  }

  enqueue(from, to, body, subject) {
//crea un nuevo objeto Mail con estos argumentos
    const newEmail = new Mail(from, to, body, subject)

    if (!this.length) {
//Si la cola está vacía (es decir, su longitud es 0), el nuevo correo electrónico se convierte en el primer y último elemento de la cola.
      this.first = newEmail
      this.last = newEmail
    } else {
//De lo contrario, se agrega al final de la cola y se actualiza el puntero last
      this.last.next = newEmail
      this.last = newEmail
    }
//actualiso la longitud
    this.length++
  }

  dequeue() {
    if (!this.length) {
//Si la cola está vacía (es decir, su longitud es 0), salta el error 
      throw new Error('La queue esta vacia')
    }
//guarda una referencia al primer elemento de la cola
    let removedMail = this.first
//Si el primer y el último elemento son iguales, solo borro el unico nodo y lo remplazo por null
    if (this.first === this.last) 
      this.last = null
    }
//el puntero se establece en el siguiente elemento en la cola y se reduce la longitud de la cola
    this.first = this.first.next
    this.length--
//destructuro para extraer las propiedades from, to, body y subject del "removeMail"
    const { from, to, body, subject } = removedMail
//las devuelve en un objeto
    return { from, to, body, subject }
  }

  peek() {
//verifica si el primer elemento de la cola es null. Si es así, devuelve null
    if (!this.first) return null
//destructuro para extraer las propiedades from, to, body y subject del "Del primer nodo de la cola "
    const { from, to, body, subject } = this.first
//las devuelve en un objeto.
    return { from, to, body, subject }
  }

  size() {
//me dice la longitud de la cola 
    return this.length
  }
}