2018校招 删除重复字符

import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class Main {
public static void main(String[] args) {
Scanner scanner=new Scanner(System.in);
String string=scanner.nextLine();
boolean flag[]=new boolean[26];
int len=string.length();
for (int i = 0; i < len; i++) {
char c=string.charAt(i);
for (int j = i+1; j < len; j++) {
if (c==string.charAt(j)) {
string=string.substring(0,j)+string.substring(j+1,string.length());
len=string.length();
j–;
}
}
}
System.out.println(string);
}
}