题解 | 不难

import java.util.*;

public class Main{ public static void main(String[] agrs){ Scanner in = new Scanner(System.in); int num = in.nextInt(); HashSet set = new HashSet(); while(in.hasNext()){ int i = in.nextInt(); set.add(i); // Collections.sort(arr,Collections.reverseOrder()); 倒叙 } List arr = new ArrayList(set); Collections.sort(arr); for (Object obj: arr) { System.out.println(obj); } } }