题解 | #字符串分隔#数字不超过10^8,用int值来存每一位数

import java.io.*;
public class Main{
    public static void main(String[] args) throws Exception{
        BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
        String str;
        while((str = bf.readLine()) != null){
            StringBuffer sb = new StringBuffer();
            int num = 0;
            for(int i = str.length() - 1;i >= 0;i--){
                if((num & (1 << (str.charAt(i) - '0'))) == 0){
                    sb.append(str.charAt(i));
                    num |= (1 << (str.charAt(i) - '0'));
                }
            }
            System.out.println(sb);
        }
            
    }
}