学步园

package 容器类;
 
import java.util.*;
 
class A3 implements Comparable{
    private int a;
    public A3(int a){
        this.a = a;
    }
    public int compareTo(Object o) {
        A3 a3 = (A3)o;
        int result = a3.a>a ? 1:-1;
        return result;
    }
    public int getA() {
        return a;
    }
}
 
public class set3 {
    public static void main(String[] args) {
        TreeSet ts = new TreeSet();
        ts.add(new A3(5));
        ts.add(new A3(4));
        ts.add(new A3(4));
        System.out.println(ts.size());
        Iterator<Object> it = ts.iterator();
        System.out.println(ts.size());
        while(it.hasNext()){
            A3 a2 = (A3)it.next();
            System.out.println(a2.getA());
        }
    }
}