import java.util.HashMap;


public class Apple {
    private String color;

    public Apple(String color) {
        this.color = color;
    }

    public boolean equals(Object obj) {
        if (!(obj instanceof Apple)) {
            return false;
        }

        if (obj == this) {
            
 
return true;
        }

        return this.color == ((Apple) obj).color;
    }

    public static void main(String[] args) {
        Apple a1 = new Apple("green");
        Apple a2 = new Apple("red");

        //hashMap stores apple type and its quantity
        HashMap<Apple, Integer> m = new
 
 HashMap<Apple, Integer>();
        m.put(a1, 10);
        m.put(a2, 20);
        System.out.println(m.get(new Apple("green")));
    }
}