Lab:  Hashing

• Collaboration is allowed on these problems.
• As with all work for this course, each problem submitted must include a complete list of all sources used (e.g., from the textbook, Web materials, conversations with other students, etc.) References must be specific, indicating publication information (e.g., publisher, date, Web site URL) or individual(s) consulted.
• Grading will be based on the insight and comprehension shown in the student work. Thus, copying an answer from another source may yield few or no points.

Hashing

A hash function returns integers between 0 and 15 based on the first letter of a data item according to the following table.

For example, according to this hash function, the string TM would hash to the value 2 (based on the initial letter T; the hash function does not look at the second letter M).

1. Consider the following sequence of 13 data items:

   UQ  GR  GD  WZ  QS  NW  DT  AX  SL  CY  EM  MR  ZB

   Suppose the above sequence is to construct each of the following data structures 16 locations (labeled 0 through 15), based on the hash function given above.

   1. Closed, unbucketed hash table, using linear probing
   2. Closed, unbucketed hash table, using quadratic probing (use both -i² and +i²)
   3. Open, bucketed hash table (with chaining)

   Show the resulting structure by filling in the following tables:

   Closed, unbucketed hash table using linear probing	Closed, unbucketed hash table using quadratic probing	Open, bucketed hash table (with chaining)
   0       1       2       3       4       5       6       7       8       9       10       11       12       13       14       15	0       1       2       3       4       5       6       7       8       9       10       11       12       13       14       15	0 ⇒   1 ⇒   2 ⇒   3 ⇒   4 ⇒   5 ⇒   6 ⇒   7 ⇒   8 ⇒   9 ⇒   10 ⇒   11 ⇒   12 ⇒   13 ⇒   14 ⇒   15 ⇒

created December, 2021 revised December-January 2021
For more information, please contact Henry M. Walker at walker@cs.grinnell.edu.