题解 | #提取不重复的整数#

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        int a = scanner.nextInt();
        int c = 0;
        Set<Integer> set = new HashSet<>();
        StringBuffer str = new StringBuffer();
        while(a > 0){
            int b = a % 10;
            a /= 10;
            if(set.add(b)){
                str.append(b);
            }
        }
        int value = Integer.parseInt(str.toString());
        System.out.println(value);
    }
}