BU CAS CS 113
Introduction to Computer Science II with Intensive C
Fall 1997

Deadline

Note: Because of the holidays, anything turned in by 11:59 pm on Monday, December 1, will count as only one day late.

What to Submit

These programs are to be electronically submitted by using the submit program on csa. The code you submit should conform with the program assignment guidelines.

Deleting from a Hash Table

/* Function: DeleteKeyFromSymbolTable
 * Usage:    value = DeleteKeyFromSymbolTable(table, key);
 * ------------------------------------------------------- 
 * This removes key (and it associated value) from table,  returning
 * the value associated with key or UNDEFINED if key is not in table.
 */

void *DeleteKeyFromSymbolTable(symtabADT table, string key);

To save space on the system and in the grader's files, please submit just the implementation of this one function in hw7-delete.c. Here are some files you might want to look at:

• hw7-delete.c (This has a non-functional delete function, but it is sufficient to compile hw7-inv and can be used as a start for your file by this name.)
• hw7-symtab.h
• hw7-symtab.c (Note how hw7-delete.c gets included into this file. This is not a standard thing to do; normally one does not include .c files inside other .c files, but it does allow us to avoid having you all submit big files with one little function added at the end.)

Using a Symbol Table

    A - Add item
    D - Delete item
    L - Lookup item
    I - print Inventory list
    < - print Inventory list for items with quantity less than specified amount
    X - print most expensive item (with price and quantity)
    Q - quit

Some of these take additional input (in order listed): A (item, price, quantity), D (item), L (item), < (quantity). Each operation which prints one or more items should give the item followed by price, followed by quantity in nice columns. (You may print only the first 15 characters of an item with a long name.) The order in which items are printed (when more than one is printed) is irrelevant and will probably be in some "random" order which depends on the hash function used. If the user tries to lookup something not in the table, an appropriate message should be displayed.

Input/Output. Each input value should be requested on a separate line. This will make your lives easiest, since you will not need to parse the input. You may read the commands as strings and then just look at the first character. (I will not require that you program handle inputs of more than one character, but this is an easy method to do so.) Thus a sample run might look like:

command (A,D,L,I,X,<,Q): A
     item: hammer
    price: 7.50
 quantity: 10

command (A,D,L,I,X,<,Q): D
     item: nails
  
     nails not present in table.  Nothing deleted.

command (A,D,L,I,X,<,Q): I

  Current Inventory
  ======= =========
  item             price     quantity
  ----             -----     --------
  hammer           7.50      10


command (A,D,L,I,X,<,Q): Q

Makefile

1. Copy this Makefile into the directory where your programs are.
2. Name it Makefile.
   • Note:If you named it Makefile.a7, you will have to use the mv (short for move) command to rename it by typing mv Makefile.a7 Makefile or the cp command to copy it by typing cp Makefile.a7 Makefile
3. type: make -k. (The -k means "keep going", which instructs make to build as much as it can, rather than quit after the first error.)

Academic Honesty and Collaboration

Do not allow your work to be used by others:

• Set the permissions so that they are not readable by others.
• Do not recycle old printouts. Take them home to throw them out.
• Do not e-mail your solution to anyone.

Warning: If someone cheats by using your work, you will also be penalized.