设计一个虚基类base，包含姓名和年龄私有数据成员以及相关的成员函数，由它派生出领导类leader，包含职务和部门私有数据成员以及相关的成员函数。再由base派生出工程师类engineer，包含职称和专业私有数据成员以及相关的成员函数。然后由leader和engineer类派生出主任工程师类chairman。采用一些数据进行测试。 -Design a virtual base class base, contains the names and ages of private data members and associated member functions derived by its leadership class leader, duties and authorities contain private data members and associated member functions. Then derived from the base class engineers, engineer, and professional titles contain private data members and associated member functions. Then the leader and chief engineer engineer class derived class chairman. Some data used for testing.