Java

When I submit my submission, grader says exit code is not zero. I'm using Scanner for reading and output my result using System.out, what could be wrong?

Edit: Ok, problem solved. Apparently, I cannot use Scanner for reading, but why??

Scanner is a part of java file access library. You can trick the scanner to read from files.

File access (file libraries) are not allowed - and not present on z-trening.