Python程序设计-AI辅助编程习题答案 第九章

1.classRectangle:def__init__(self,height,width):self.height=heightself.width=widthdefarea(self):returnself.height*self.widthrectangle=Rectangle(5,10)area=rectangle.area()print("矩形的面积为：",area)2.classRectangle:def__init__(self,height,width):self.height=heightself.width=widthdefarea(self):returnself.height*self.widthclassSquare(Rectangle):def__init__(self,height):self.height=heightself.width=heightdefarea(self):returnself.height*self.widthsquare=Square(5)area=square.area()print("正方形的面积为：",area)3.classStudent:"""学生类，存储个人信息和成绩"""def__init__(self,student_id,name):self.student_id=student_id=nameself.grades={}#存储课程成绩，格式:{课程名:分数}defadd_grade(self,course,score):"""添加或更新课程成绩"""self.grades[course]=scoredefget_average(self):"""计算平均成绩"""ifnotself.grades:return0returnsum(self.grades.values())/len(self.grades)def__str__(self):returnf"学号:{self.student_id},姓名:{},平均成绩:{self.get_average():.1f}"classGradeManager:"""成绩管理类，管理多个学生"""def__init__(self):self.students={}#存储学生，格式:{学号:学生对象}defadd_student(self,student):"""添加学生"""ifstudent.student_idnotinself.students:self.students[student.student_id]=studentreturnf"添加成功:{}"returnf"错误:学号{student.student_id}已存在"defget_student(self,student_id):"""查询学生"""returnself.students.get(student_id,None)defshow_all_students(self):"""显示所有学生信息"""ifnotself.students:return"暂无学生信息"return"\n".join(str(s)forsinself.students.values())#使用示例if__name__=="__main__":#创建成绩管理器manager=GradeManager()s1=Student(101,"张")s2=Student(102,"李四")print(manager.add_student(s1))print(manager.add_student(s2))s1.add_grade("数学",90)s1.add_grade("英语",85)s2.add_grade("数学",88)s2.add_grade("英语",92)print