Exercise for Week Four.
Consider a program to carry out Roman arithmetic. This will need
to contain two conversion modules, one to convert from a string to be interpreted
as a Roman numeral to an integer value and the other to convert from an integer
value to a string which represpents that integer value. (You need not consider the
later version with IV for 4, only the version IIII).
Produce Z specifications for each of these modules. Complete them in time to hand in
by noon on Tuesday.
Remember your Z specification does not contain flow-charts, pseudo code or other
ways of describing how the module achieves its result. It gives a very precise
definition of the valid input to a module, the valid output from a module, and the
relationship between them. Consequently the specifications of these modules will
be so short you may not believe they can be correct. Have faith and hand in what
your have produced.