Needed: A function
h that maps a key in a large set
U of
possible keys to a small set of possible array indexes of size
m.
- h : U → {0, 1, ... m-1}
where m is small enough to be the size of a storeable
array
- h : {1, 2, ... 999999999} → {0, 1, ... m-1}
from the previous example
- h performs a key-to-index or key-to-address
transformation.
- h is called a hash function