Java HM

import java.io.*;
import java.text.*;
import java.util.*;
import java.math.*;
import java.util.regex.*;

public class Main {

  public static void main(String[] args) {
    Map<Object, Object> test = new HashMap<>();

    test.put(0, 23);
    test.put(1, "hello");
    test.put(15, 34.5);
    test.put("mamma mia!", 42);

    System.out.println(test.get("mamma mia!").equals(42));
    System.out.println(test.get(1).equals("hello"));
  }
}