какого он от меня хочет

Exception in thread "main" java.lang.IndexOutOfBoundsException at java.base/java.io.FileOutputStream.writeBytes(Native Method) at java.base/java.io.FileOutputStream.write(FileOutputStream.java:348) at com.javarush.task.task18.task1808.Solution.main(Solution.java:25) BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); FileInputStream fis1 = new FileInputStream(br.readLine()); FileOutputStream fos1 = new FileOutputStream(br.readLine()); FileOutputStream fos2 = new FileOutputStream(br.readLine()); byte[] buffer = new byte[fis1.available()]; int count; if (fis1.available() % 2 == 0) { count = fis1.read(buffer); fos1.write(buffer,0,((buffer.length)/2)-1); fos2.write(buffer,(buffer.length/2),count); fis1.close();fos1.close();fos2.close();