當用戶輸入密碼時候，如果輸入正確會輸出welcom user login，如果輸入錯誤會輸出invalid username or password

#!/usr/bin/env   python
# -*- coding:utf-8 -*-
import getpass
_username = "xcn"
_password = "admin"
username = input("username:")
password = getpass.getpass("password:")
print(username, password)
if _username == username and _password == password:
    print("welcome user {name} login ..." .format(name=username))
else:
    print("invalid username or password!")
    
ce

#!/usr/bin/env   python
# -*- coding:utf-8 -*-
age_of_xcn = 20
guess_age = int(input("guess age:"))
if guess_age == age_of_xcn:
    print("yes,you got it")
elif guess_age > age_of_xcn:
    print("think smaller")
else:
    print("think bigger")
  
 
執行結果：
guess age:12
think bigger


guess age:22
think smaller

本文出自 “小菜鳥” 博客，請務必保留此出處http://baishuchao.blog.51cto.com/12918589/1932908

流程判斷（if...else）