import java.util.ArrayList; import java.util.Collections; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Scanner; import java.util.Set; import java.util.stream.Collectors; // 注意类名必须为 Main, 不要有任何 package xxx 信息 public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); int length=in.nextInt(); Set<Integer> set=new HashSet<>(); while (in.hasNextInt()) { // 注意 while 处理多个 case int a = in.nextInt(); set.add(a); } Iterator<Integer> iterator=set.iterator(); List<Integer> list=set.stream().collect(Collectors.toList()); Collections.sort(list); list.forEach(i->System.out.println(i)); } }