字符串去重

import java.util.*;
import java.lang.*;
public class Main{
    public static void main(String [] args){
        Scanner scan=new Scanner(System.in);
        while(scan.hasNext()){
            String s=scan.next();
            LinkedHashSet<Character> set=new LinkedHashSet<>();
            for(int i=0;i<s.length();i++){
                char temp=s.charAt(i);
                set.add(temp);
            }
            StringBuffer sb=new StringBuffer();
            Iterator iterator=set.iterator();
            while(iterator.hasNext()){
                Object c=iterator.next();
                sb.append(c);
            }
            System.out.println(sb.toString());
        }
    }
     
     
}