[SOLVED] Unsafe or unchecked Operation in line 57

Question

Can someone explain why I get this compiler warning (at line 57) . And how to prevent this.
The output at this point is as expected.
https://code.sololearn.com/cbL2ZJT3dBA7/?ref=app

Answer 1

When you declare
private TreeMap<Integer,SortedSet>
visited_fields;

Don't forget to put in SortedSet's generic type in there as well
Fix:

private TreeMap<Integer,SortedSet<Integer>>
visited_fields;

Or you could just put

@SuppressWarnings("unchecked")

Over the move method just to ignore it, but it's not a fix.

Answer 2

Odyel
Thank you. That works. Very nice 👍