Hash collision: if two keys "hash" to the
    same index, it's a "hash collision"

  (1) Use a linked list at the given index

  (2) Repeatedly add 1 to the given index
         until we find a free spot

  vector:
 -----------
0|    0    |     begin():
 -----------   ------------  ---------
1|    -------->| Morrison -->| Zebra |
 -----------   ------------  ---------
2|    0    |
 -----------   ---------------
3|    -------->| Goldschmidt |
 -----------   ---------------
4|    -------->| Jones |
 -----------   ---------
   etc.
 -----------   ---------
9|    -------->| Smith |     ...end()
 -----------   ---------

Iterator on a hash table:
  Morrison  Zebra  Goldschmidt  Jones  Smith



 FINAL EXAM
========================================
 Comprehensive

 Coverage is Test 1, Test 2, Trees

 3-5 questions
 ---- trees
 ---- characters/string operations
           (isalpha tolower)