что надо сделать?
package com.javarush.task.task18.task1808;
/*
Разделение файла
*/
import java.io.*;
public class Solution {
public static void main(String[] args) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
String file1 = reader.readLine();
String file2 = reader.readLine();
String file3 = reader.readLine();
FileInputStream input = new FileInputStream(file1);
byte[] buf = new byte[input.available()];
input.read(buf);
input.close();
int middle= (int) Math.round(buf.length/2);
FileOutputStream output = new FileOutputStream(file2);
for(int j = 0; j<middle;j++){
output.write(buf[j]);
}
output.close();
FileOutputStream output2 = new FileOutputStream(file3);
for(int k = middle; k<buf.length;k++){
output.write(buf[k]);
}
output2.close();
}
}