CSE 232 Spring 2012

Computer Project #3 -- C++ Control Structures

Assignment Overview:

  This assignment focuses on the design, implementation and testing of C++
  functions which use control structures.  You will develop two functions
  which will complete the program described below.

  It is worth 30 points (3% of course grade), and must be completed no later
  than 11:59 PM on Thursday, February 2.

Assignment Specifications:

  1) The program will compute and display information for a utility company
  which supplies water to its customers.  For a specified customer, the
  program will compute and display the amount of money which the customer will
  be charged for water usage during the current billing period.

  2) The program will be composed of three functions:  "main", "gallons", and
  "fee".  The instructor will supply function "main"; you will supply the
  other two functions.

  3) Function "main" will perform all input and output operations.  It will
  call functions "gallons" and "fee" as needed to compute the desired output.

  Function "main" will repeatedly prompt the user to enter the billing code
  for a given customer, as well as the two meter readings for that customer.
  It will then process that customer's information and display the results.
  It will halt when the user enters "end-of-file" (control-d) instead of a
  billing code.

  4) Function "gallons" will be declared as:

    double gallons( int, int );

  where the first argument represents the beginning meter reading and the
  second argument represents the ending meter reading (assume that the meter
  is read by a representative of the utility company at the beginning and
  ending of the billing period).  The readings are taken from a meter which
  has nine digits and records tenths of a gallon.

  Function "gallons" will return the number of gallons of water used by the
  customer during the current billing period.

  Note that the meter's dial has nine digits and records tenths of a gallon.
  For example, assuming that the beginning reading was 444400003 and the
  ending reading was 444400135, then the customer used 13.2 gallons of water
  during the billing period.

  Also, note that the reading at the end of the billing period may be less
  than the reading at the beginning of the billing period, since the meter's
  dial has only nine digits.  For example, assuming that the beginning reading
  was 999999997 and the ending reading was 000000005, then the customer used
  0.8 gallons of water during the billing period.



  5) Function "fee" will be declared as:

    double fee( char, double );

  where the first argument represents the billing code of the customer ('R',
  'C' or 'I'), and the second argument represents the gallons of water used by
  the customer during the current billing period.

  Function "fee" will return the amount of money that the customer will be
  charged, based on the customer's billing code and water usage, using the
  following information.

    Code 'R' (residential):

      $5.00 plus $0.0005 per gallon used

    Code 'C' (commercial):

      $1000.00 for 4 million gallons or less, and $0.00025 for each
      additional gallon used

    Code 'I' (industrial):

      $1000.00 if usage does not exceed 4 million gallons; $2000.00 if usage
      exceeds 4 million gallons but does not exceed 10 million gallons; and
      $2000.00 plus $0.00025 for each additional gallon if usage exceeds 10
      million gallons.

  Function "fee" will return a value of zero for an unrecognized billing
  code.

Assignment Deliverables:

  The deliverables for this assignment are the following files:

    proj03.support.cpp -- the source code for your functions
    proj03.support.h   -- the interface to your functions

  Be sure to use the specified file names, and to submit your files for
  grading via the "handin" system.

Assignment Notes:

  1) Please note that the final versions of your functions will not perform
  any input or output operations, although you may wish to display selected
  values while you are developing your functions.

  2) The instructor will supply the following file:

    /user/cse232/Projects/project03.driver.o

  where "project03.driver.o" contains the object code for function "main".

  3) Use the following command to compile and link the program:

    <prompt> g++ proj03.support.cpp /user/cse232/Projects/project03.driver.o

  where "proj03.support.cpp" is the name of your source code file.