python基础

#第一个python程序
# print(‘hello world‘)
# print(‘你好，世界‘)
# print(‘alex‘,‘wusir‘,sep=":")
# print(‘alex‘,end="\t")
# print(‘wusir‘)
# print(‘hello world‘,file=open(‘hello.txt‘,‘w‘,encoding=‘utf-8‘))

#变量的命名规范
# AgeOfAlex=18#驼峰体
# age_of_alex=18#下划线

#查看数据类型type
# print(type(12))
# print(type(‘hello‘))
# print(type([1,2]))
# print(type((1,2,3)))
# print(type({"1":"2"}))
# print(type({‘1‘,2}))
# print(type(True))
# print(type(range))
# def hello():
#     print(‘hello‘)
# print(type(hello))
# class Student():
#     pass
# a=Student()
# print(type(a))

#引号
# print(‘I am a student‘)
# print("I‘m a student")
# msg="""
# 会当凌绝顶，
# 一览众山小。
# """
# print(msg)

#用户交互input
#input得到的是字符串
# name=input(‘请输入你的名字:‘)
# age=input(‘请输入你的年龄:‘)
# print(name,age)
# print(type(name),type(age))

#条件控制语句if elif else
# score=int(input(‘请输入你的成绩:‘))
# if score>90:
#     print(‘优秀‘)
# elif score>80:
#     print(‘良好‘)
# elif score>70:
#     print(‘一般‘)
# elif score>60:
#     print(‘及格‘)
# else:
#     print(‘不及格‘)

#条件语句的嵌套
# name=input(‘name:‘)
# age=int(input(‘age:‘))
# if name==‘alex‘:
#     if age==18:
#         print(‘welcome‘)
#     else:
#         print(‘age error‘)
# else:
#     print(‘name error‘)

#循环语句 while for
# count=1
# s=0
# while count
#     s+=count
#     count+=1
# print(s)

# s=0
# for i in range(1,101):
#     s+=i
# print(s)

#break continue else
# count=0
# while count
#     count+=1
#     if count==3:
#         break
#     print(count)
# else:
#     print(‘循环正常结束后执行‘)

# count=0
# while count
#     count+=1
#     if count==3:
#         continue
#     print(count)
# else:
#     print(‘循环正常结束后执行‘)

#标志位
# flag=True
# count=1
# while flag:
#     print(count)
#     count+=1
#     if count>100:
#         flag=False