python学习之路day1

学习总结：

　　变量，字符的由来，python2和python3的区别，控制语句：if，for，while，break，continue用法

学习示例：

　if用法1：判断年龄

 # -*- coding: utf-8 -*-
 # Author:Yang Hang

 age = 75

 guess_age = input("请输入年龄：")
 guess_age = int(guess_age)

 if guess_age == age:
     print("你猜对了！")
 elif guese_age > age:
     print("请往小的猜！")
 else:
     print("请往大的猜！")

　　if用法2：登陆示例

 # -*- coding: utf-8 -*-
 # Author:Yang Hang

 _username = 'yanghang'
 _passwd = '

 username = input("username:")
 passwd = input("password:")

 if username == _username and passwd == _passwd:
     print("成功登陆！")
 else:
     print("用户名或密码有误，请重新输入！")

　　for用法1：输出1到10

 # -*- coding: utf-8 -*-
 # Author:Yang Hang

 for i in range(10):
     print("loop",i)

　　for用法2：猜年龄

 # -*- coding: utf-8 -*-
 # Author:Yang Hang

 age = 75
 count = 0

 for i in range(3):
     guess_age = int(input("请输入年龄："))
     if guess_age == age:
         print("恭喜你猜对了！")
         break
     elif guess_age > age:
         print("请往小的猜！")
     else:
         print("请往大的猜！")
 else:
     print("输入次数超过三次，结束")

　　while用法1：

 # -*- coding: utf-8 -*-
 # Author:Yang Hang

 count = 0
 while count < 100:
     print("count:",count)
     count = count +1

　　while用法2：

 # -*- coding: utf-8 -*-
 # Author:Yang Hang

 age = 75
 count = 0
 '''
 #版本1:
 while True:
     if count == 3:
       print("输入次数超过三次，结束")
         break
 guess_age = int(input("请输入年龄："))
 if guess_age == age:
     print("恭喜你猜对了！")
     break
 elif guess_age > age:
     print("请往小的猜！")
 else:
     print("请往大的猜！")
 count += 1
 '''
 #优化版本
 while count <3:
     guess_age = int(input("请输入年龄："))
     if guess_age == age:
         print("恭喜你猜对了！")
         break
     elif guess_age > age:
         print("请往小的猜！")
     else:
         print("请往大的猜！")
     count +=1
     if count == 3:
         countine_confirm =input("你还想继续猜吗..?")
         if countine_confirm != 'n':
             count = 0
 else:
     print("输入次数超过三次，结束")