login you wan 不加引號 dbo 變量 判斷 lse put

import getpass
username = input("username:")
password = getpass.getpass("password:")

例1

_username = "wang" //賦值要加雙引號 如果不加引號 username = wang，這裏的wang也代表變量
_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")

輸出結果：
username:qang
password:113
invalid username or password

username:wang
password:123
welcome user wang login

例2：
_username = "wang"
_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")
print("123") //只要是自成一派的都要頂格寫，不屬於if else的子程序，所以會一直輸出

輸出結果：
username:wang
password:123
welcome user wang login
123

例3：加判斷語句

age_of_oldboy=56
guess_age=int(input("guess_age:"))
if age_of_oldboy==guess_age:

print("yes,you got it!")
elif age_of_oldboy>guess_age:
print("think smaller")
else:
print("think older")

輸出結果：
guess_age:56
yes,you got it!
guess_age:57
think older
guess_age:20
think smaller

第十一節 if else流程判斷