1.编写程序, 编写一个学生类, 要求有一个计数器的属性, 统计总共实例化了多少个学生
代码语言：javascript复制class Student:
count=0
def __init__(self,name,age,gender):
self.name=name
self.age=age
self.gender=gender
Student.count =1
ming=Student("小明",25,"male")
hong=Student("小红",25,"female")
lan=Student("小兰",25,"female")
print(Student.count)2、人狗大战
代码语言：javascript复制class Person:
def __init__(self,name,aggr,hp,level):
self.name=name
self.aggr=aggr
self.hp=hp
self.level=level
def atta(self,dog):
dog.hp-=self.aggr
print("%s踢了一脚%s,%s掉了%s点血" % (self.name, dog.name, dog.name, self.aggr))
class Dog:
def __init__(self,name,aggr,hp,kind):
self.name=name
self.aggr=aggr
self.hp=hp
self.kind=kind
def bite(self,person):
person.hp-=self.aggr
print("%s咬了一口%s,%s掉了%s点血"%(self.name,person.name,person.name,self.aggr))
guo=Dog("果果",25,100,"金毛")
ming=Person("小明",25,100,15)
guo.bite(ming)
ming.atta(guo)
print(ming.__dict__)
print(guo.__dict__)3、正方形周长和面积
代码语言：javascript复制class Square:
def __init__(self,r):
self.side=r
def peri(self):
return "周长是%s"%(4*self.side)
def area(self):
return "面积是%s"%(self.side**self.side)
s=Square(2)
print(s.peri())
print(s.area())
