How to use two numbers as a Map key

Question

I have two numbers and I want to use them together as a key in a Map. Currently, I\'m concatenating their string representations. For example, suppose the key n

Answer 1

Create an object that holds the two numbers and use it as the key. For example:

class Coordinates {

  private int x;
  private int y;

  public Coordinates(int x, int y) {
     ...
  }

  // getters

  // equals and hashcode using x and y
}

Map locations = new HashMap();

If you prefer a mathematical approach, see this StackOverflow answer.