sem1-tips.md

@@ -5,6 +5,8 @@
 * In A3 'Bedre gulrøtter', we want you to write down what would be required to get Carrot to do something at each turn, but you do not need to implement this in the code (this would make the rest of the assignment more difficult).   
 * In assignments where there are multiple steps, you do not hand in partial solutions: just handing in the final code is enough. If you do go for crazy experiments in part C, you do need to save and submit part B first.
 * In B3, instead of inserting items in sorted order as suggested in the text, you can also insert at the end and sort the whole list afterwards by using [java.util.Collections.sort(list)](https://docs.oracle.com/javase/7/docs/api/java/util/Collections.html#sort(java.util.List)), but then you would need to reverse the order afterwards.
+* Når du implementerer `IItem` _(dette betyr også interfaces som extender `IItem`, som `IActor`)_  må du sette `getSymbol()` til å returnere et symbel istedet for `null`. Hvis den er `null` vil du få en stack trace (kræsj rapport) som ikke inneholder noen av klassene du har endret.
+  * Vær spesielt varsom når du du først implementerer Player i `B2 a)`
 
 ## Testing