Python入门小练习

#输出，输入，类，构造方法
import math
s = 'Hello world!'
print('你好，Aurora!!!')
print(math.log2(8))
print('helao'[3])
print(len("12316465159651"))
print(type(3.14))
print(type(True))
print(s[6])

use_age = int(input('请输入年龄\n'))
print("你的年龄是"+str(use_age)+"岁")

a = int(input("输入\n"))
if a == 1:
    print("ooo")
elif a==2:
    print("aaa")
elif a== 9:
    print("adasd")
else:
    print("asdsad4")

class Student:
    def __init__(self,name ,id):
        self.name = name
        self.id = id;
        self.grade = {"语文":0,"数学":0}

    def set_grade(self,crouse,grade):
        if crouse in self.grade:
            self.grade[crouse]=grade;
chen = Student("小陈","10086")
print(chen.name)
chen.set_grade("数学",95)
print(chen.grade)

#读写文件

with open("./poem.txt","w",encoding="utf-8")as f:
    f.write("123\n456\n789")

 追加

with open("./poem.txt","a",encoding="utf-8")as f:
    f.write("123\n456\n789")