import java.util.HashMap;

public class Task301025 {
    public static void main(String[] args) {
        HashMap<Key, String> map = new HashMap<>();
        
        Key k1 = new Key(1);
        Key k2 = new Key(1);
        Key k3 = new Key(2);
        
        map.put(k1, "first");
        map.put(k2, "second");
        map.put(k3, "third");
        
        k1.value = 2;
        
        System.out.println(map.get(k1));
        System.out.println(map.get(k2));
        System.out.println(map.get(k3));
        System.out.println(map.size());
    }
    
    static class Key {
        int value;
        Key(int value) { this.value = value; }
        
        public boolean equals(Object o) {
            return o instanceof Key && ((Key) o).value == this.value;
        }
        
        public int hashCode() {
            return value;
        }
    }
}