Почему валидатор не принимает решение?
package com.javarush.task.task18.task1801;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.TreeSet;
/*
Максимальный байт
*/
public class Solution {
public static void main(String[] args) throws Exception {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
TreeSet<Integer> ts_bytes = new TreeSet<>();
String file_name = reader.readLine();
FileInputStream inputstream = new FileInputStream(file_name);
try {
while (inputstream.available() > 0){
ts_bytes.add(inputstream.read());
}
} catch (IOException e){
System.err.println(e.getStackTrace());
} finally {
inputstream.close();
}
System.out.println(ts_bytes.last());
}
}