Each piece can then be described informally with a commentary. The Z schemes describe the dynamic and static aspects of a system. The static aspect of a system includes the states the system can occupy and the relationship maintained when the system transits from state to state. The dynamic aspects include the operation that are possible, the changes that occur and the input - output relationship.

(1) The list of persons name and corresponding salaries (can be used by a company to store data of the employees working in that company and also store the salaries of these people.) the reasons for using this type of data are

Several people using one name may earn the same salary, the system can be coded to display number of people earning the same salary, this means that the tests data type can be subjected to various operations.

To test for rotation a number (i) and the square of the number (i2) can be used. The test data comprise of different numbers and their squares, these numbers form a sequence. The elements can be arranged so that the top most elements are the first members of the given sequence and the last element is greatest number in that list. On rotating left the greatest number and its square becomes the first element of the set. ...