Topic 02
d)
additional contract for a set: * in a set containing X, add X throws an IllegalArgumentException * in a set, add not integer throws an IllegalArgumentException * in a set containg elem X, the function contains must return True * in set containing X and Y, intersects should return true to set of X and Y * in two sets with the same elements created in difference instances, equals has to return True
All new tests passed.
e)
According to Jacoco report, UI class does not have too much coverage, and in sets there is no branch coverage for different situations;
