Question

All valid hash functions have the property that if two objects are equal under the equals method, then they also have equal _____ _____.

a) Hash values
b) Attributes
c) Methods
d) Comparators

Answer 1

If two objects are equal under the equals method, they must have equal hash values, which is a property of all valid hash functions used in data structures like hash tables.

Step-by-step explanation:

All valid hash functions have the property that if two objects are equal under the equals method, then they also have equal hash values. This is essential for ensuring that objects can be correctly identified and retrieved from data structures that use hashing, like hash tables. In a hash table, objects with the same hash value are considered to be the same item for storage and retrieval purposes.

It is important to note that while equal objects must have equal hash values, the reverse is not necessarily true; different objects can have the same hash value, which is known as a collision. However, a well-designed hash function will minimize collisions to maintain efficiency.

The answer to the student's question is: a) Hash values.