Python学习笔记_1_基础_1：变量、判断、循环语句

一、充满仪式感的Hello Word

print("Hello Word!")

二、变量定义赋值

name = 'cz'
print("My name is ",name)
name2 = name
print(name,name2)
name = "xiaohui"
print(name,name2)

 

 三、注释

单行注释：#我是注释，别离我。

多行注释："""  我是注释，别离我。 """

另外多行注释还可以定义多行字符串：

msg = """aaa
bbb
ccc
"""
print(msg)

四、用户输入

username = input('username: ')

print(username)

获取用户输入信息，并赋值给变量。

 五、字符串拼接

name = input('name:')
age = int(input('age:'))
print(type(age))
job = input('job:')
salary = input('salary:')

info2 = '''
---------------info of {_name}------------
Name:{_name}
Age:{_age}
Job:{_job}
Salary:{_salary}
'''.format(_name=name,_age=age,_job=job,_salary=salary)

print(info2)

 

name = input('name:')
age = int(input('age:'))
print(type(age))
job = input('job:')
salary = int(input('salary:'))
print(type(salary))

info2 = '''
 ---------------info of %s------------
 Name:%s
 Age:%d
 Job:%s
 Salary:%d
 '''%(name,name,age,job,salary)

print(info2)

 

六、表达式：if..else

 1、用户登录验证

_username = 'cz'
_password = '123'

username = input('username: ')
password = input('password: ')


if _username == username and _password == password:
    print('Welcome user {name} login...'.format(name=username))
else:
    print('Invalid username or password!')

七、表达式：while loop

age_of_aa = 56
count = 0
while count<=2:
    guess_age = int(input('guess age: '))

    if guess_age == age_of_aa:
        print('yes,you got it!')
        break
    elif guess_age > age_of_aa:
        print('think,please guess smaller!')
    else:
        print('think,please guess bigger!')

    count = count +1   #count +=1

else:
    print('you have tried too many times..fuck ...!')

* while 后也可以跟esle，代表while 判断为false时执行。老牛逼了！

八、表达式：for loop

for i in range(10):
    if i<3:
        print('loop ',i)
    else:
        continue

*continue：代表跳过当前循环，进入下一次循环！