1.定义Point类，有坐标_x,_y两个成员变量；对Point类重载“

++”（自增）、“--”自减运算符，实现对坐标值的改变

2.定义一个车（vechical）基类，有Run。Stop等成员函数，由此派生出自行车（bicycle）类，汽车（motorcar）类，从bicycle和motorcar派生出摩托车（motorcycle）类，他们都有Run，Stop等成员函数。观察虚函数的作用

3.对实验六中的people，类重载“==”运算符，“==”运算符判断两个people类对象的id属性是否相等；“=”运算符实现people类对象的赋值操作-1. The definition of Point class, there are coordinates _x, _y two member variables　on the Point class overload " ++"　(since by )," --"　from reduced operator, to realize the change of coordinates 2. Define a car (vechical) base class, there Run. Stop and other members of the function and derives a bike (bicycle), automobiles (motorcar) class, derived from the bicycle and motorcar motorcycle (motorcycle) class, they have Run, Stop and other members of the function. Observe the role of virtual function 3. On the experiment in six people, class overloaded " =="　operator ," =="　operator to judge two people of the id attribute class object are equal　" ="　operator to achieve class people Object assignment