Practice with fractions

Problem statement

Write a program to test a student's understanding of arithmetic with rational numbers (fractions). For example:

3/2 + 1/3 is 11/6

5/4 * 2/9 is 5/18

etc.

Procedure

Follow these steps to end up with a sucessful program:

1. The problem statement is given above.
2. Write the problem description.
3. Do the analysis for object design, choosing suitable representations for the class members. Write the object design down.
4. Do the analysis for process design, adding suitable function members to your classes with appropriate parameters. The application class with have (at least) a function member run. The class for fractional numbers must have (at least) overloaded operators for +, -,*, /, assignment (=) and equality (==).
5. Write C++ program code from your analysis in 3 and 4.
6. Create a source file using the editor.
7. Compile the source code using g++.
8. The program should present a random problem to the students, read the student's answer and check it against the actual value.
9. Deliverables:
• your design document with its four sections: problem statement, problem description, object design and process design.
• your source code, suitably commented and with good layout
• the output produced by the program with the tests as given in 8.
• your source code e-mailed to the grader, login name iflores.

Notes and hints

• Keep your classes to the minimum necessary (but use an application class)
• Keep the member representations as simple as possible. You do not need anything more fancy than base types
• Keep all data private: use accessor functions to selectively open up access to other classes. Don't use global variables!!
• display the result to the student in its simplest form -- use this version greatest common divisor -- make it a private function:

       long gcd(long x, long y) {

          return (x == 0) ? y : gcd(y % x, x);

       }

• use this format for inputting fractions: <numerator>/<denominator>, e.g. 1/2, 25/7, etc. You will need to check for correct format on input of the answer. Prompt the user for this input
• Use this for generating random integers:

     #include <ACG.h>

     #include <RndInt.h>

     ...

     RandomInteger n(1, 10, new ACG);

     ...

        n() // each "call" produces a different value

• end of input on UNIX is signalled by typing ctrl-D on a line by itself (ctrl-Z in DOS)
• display screen output with reasonable layout
• use cin and cout, not printf and scanf
• when you are ready to produce the final output of the program, redirect the standard input to cin from a file, and output produced by cout into a file by typing:
  a.out > outputfile < inputfile
outputfile can then be printed on the lineprinter.
• mail your source code with:
  mail iflores < filename.cc