import java.util.HashMap;

public class Maps {

public static void main(String[] args) {

// Declaración y creacion

HashMap<String, String> names = new HashMap<>();

var numbers = new HashMap<Integer, String>();

// Tamaño

System.out.println(names.size());

// Añadir elementos

names.put("Hector", "hvaron@gmail.com");

names.put("Fabio", "fabio@gmail.com");

names.put("Mariana", "mariana@gmail.com");

System.out.println(names.size());

System.out.println(names);

// Acceder a los elementos

System.out.println(names.get("Hector"));

System.out.println(names.get("Dev"));

// Verificar elementos

System.out.println(names.containsKey("Hector"));

System.out.println(names.containsKey("Dev"));

System.out.println(names.containsValue("hvaron@gmail.com"));

// Eliminar elementos

System.out.println(names.remove("Fabio"));

System.out.println(names);

// Limpiar HasMap

names.clear();

System.out.println(names);

// Modificación de elementos

names.put("Alexa", "alexa@gmail.com");

System.out.println(names);

names.put("Alexa", "alexandra_santoya");

System.out.println(names);

names.replace("Alexa", "alexa_santoya@yahoo.com");

System.out.println(names);

names.putIfAbsent("Mariana", "marianatovar@yahoo.com");

System.out.println(names);

// Otras operaciones

System.out.println(names.isEmpty());

System.out.println(names.values());

System.out.println(names);

}

}