题解HJ9 | #提取不重复的整数#

import java.util.LinkedHashSet;
import java.util.Scanner;
import java.util.Set;

// 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 x = in.nextInt();

        Set<Integer> set = new LinkedHashSet<>();

        while (x > 9) {
            set.add(x % 10);
            x /= 10;
        }
        if (x > 0) set.add(x);

        set.stream().forEach(s -> System.out.print(s));
    }
}

LinkedHashSet的简单应用