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--- public:t-622-arti-13-1:lab_3_-_hashing_states [2013/02/07 11:13] – stephan
+++ public:t-622-arti-13-1:lab_3_-_hashing_states [2024/04/29 13:33] (current) – external edit 127.0.0.1
@@ Line 15: / Line 15: @@
 ===== Hints =====
-  * You need to implement the methods [[http://docs.oracle.com/javase/6/docs/api/java/lang/Object.html#hashCode%28%29|''int hashCode()'']] and [[http://docs.oracle.com/javase/6/docs/api/java/lang/Object.html#equals%28java.lang.Object%29|''boolean equals(Object o)'']] in classes State and Position appropriately.
+  * You need to implement the methods [[http://docs.oracle.com/javase/6/docs/api/java/lang/Object.html#hashCode%28%29|int hashCode()]] and [[http://docs.oracle.com/javase/6/docs/api/java/lang/Object.html#equals%28java.lang.Object%29|boolean equals(Object o)]] in classes State and Position appropriately.
+  * For two states ''s1'' and ''s2'' that you'd consider the same, ''s1.equals(s2)'' must return true and false otherwise.
+  * For any two objects ''o1'' and ''o2'', if ''o1.equals(o2)'' then ''o1.hashCode() == o2.hashCode()'' must be true!
+  * Objects that are not equal are allowed have the same hash code. However, if that happens too often then hash maps become very inefficient.
 ===== Handing In =====