Подскажите, в чем ошибка
package com.javarush.task.task18.task1805;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.util.Set;
import java.util.TreeSet;
import java.util.*;
/*
Сортировка байт
*/
public class Solution {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
FileInputStream inputStream = new FileInputStream(reader.readLine());
ArrayList<Integer> arr = new ArrayList<>();
while (inputStream.available() > 0)
{
arr.add(inputStream.read());
}
inputStream.close();
reader.close();
Collections.sort(arr);
for (int i = 0; i < arr.size() - 1; i++){
if(arr.get(i) == arr.get(i+1))
arr.remove(i);
}
for(int i = 0; i < arr.size(); i++)
System.out.print(arr.get(i) + " ");
}
}