day4 class work

时间：2017-10-23 23:57:11 阅读：378 评论：0 收藏：0 [点我收藏+]

今天是第四天，一如既往的每天都有不会做的内容，然后还是那种你使劲的绞尽脑汁都想不出来的问题，而且还得是别人提示着，讲着，演示着才能明白的，过后自己还得使劲捉摸才能慢慢吃透。一开始还挺顺利的，还以为自己终于能够跟上一点点步伐了呢，谁知道自己高兴太早了，后面的题都不会做。。。每天都是满满的不会做，不行，搞不定，太受挫了。。。。心酸！一想到自己以后还有几十年的人生要过，就不能轻易的投降了，硬着头皮上吧，就像老师说的看不懂就硬看，逼出来就好了。

#1，索引和切片 [起始位置:结束位置:步长] 
# s1 = ‘python全栈8期‘ #索引从0开始 [索引（下标，index）] 
# print(s1[0]) 
# print(s1[3]) 
# print(s1[5]) 
# print(s1[6]) 
# print(s1[-1]) 
#切片 顾头不顾腚 
# print(s1[0:6])
# print(s1[6:10])
# print(s1[6:11]) 
# print(s1[6:]) 
# print(s1[1:5]) 
#pto #s1 = ‘python全栈8期‘ 
# print(s1[0:5:2]) 
# print(s1[0:7:3]) 
#倒取值：加步长 
# print(s1[3::-1])
# print(s1[5:0:-2]) 
# print(s1) 
#不变 
# s2 = s1[0:6] 
# print(s2)   ret = ‘alexS‘ 
#字符串的使用方法。 
# * capitalize 首字母大写,其他的全小写 ret1 = ret.capitalize() 
# print(ret,ret1)  
# * upper,lower ret2 = ret.upper() ret3 = ret.lower() 
# print(ret2,ret3) 
‘‘‘ code = ‘A‘ 
your_code = input(‘请输入验证码，不区分大小写‘) 
if your_code == ‘A‘ or your_code == ‘a‘:     
print(‘您输入的正确‘) 
else:print(‘请重新输入‘)  
code = ‘adeE‘.upper() 
your_code = input(‘请输入验证码，不区分大小写‘).upper() 
if your_code == code:    
print(‘您输入的正确‘) 
else:print(‘请重新输入‘) ‘‘‘ 
# 大小写翻转 
# ret4 = ret.swapcase() 
# print(ret4) 
# ret11 = ‘alex+jin wu‘ 
#以特殊符号或者空格隔开，每一个字符串首字母大写 title() 
# print(ret11.title()) 
# *  居中 ret = ‘alexS‘ 
# print(ret.center(20)) 
# print(ret.center(20,‘*‘))  
# *******alexS********  
# * 返回bool值  startswith endswith 
# ret5 = ret.startswith(‘a‘) 
# ret5 = ret.startswith(‘ale‘) 
# ret5 = ret.startswith(‘alexS‘) 
# ret5 = ret.startswith(‘l‘,1,3)  
# 切片 # print(ret5) 
# ret6 = ret.endswith(‘S‘,-2,) 
# print(ret6) ret22 = ‘alexS,aeaeQ‘ 
# ** count 
# ret7 = ret22.count(‘a‘) 
# ret7 = ret22.count(‘ale‘)  
# 整体与个体 
# ret7 = ret22.count(‘W‘)  
# 0 
# ret7 = ret22.count(‘a‘,0,7)  
# 切片的count 
# print(ret7)  
# a2 = "qwaaaaaaaa\taa" 
#\t前面的补全 
# 默认将一个tab键变成8个空格，如果tab前面的字符长度不足8个，则补全8个，如果tab键前面的字符长度超过8个不足16个则补全16个，以此类推每次补全8个。 
# ret8 = a2.expandtabs() 
# print(ret8,len(ret8))  ret = ‘aleaxS‘ 
# * find 通过元素找到索引(找到第一个元素)，找不到返回-1 
# ret9 = ret.find(‘a‘) 
# # ret9 = ret.find(‘W‘,0,5) 
# print(ret9) 
# #index 和find用法一模一样，找不到元素，就会报错 
# ret10 = ret.index(‘w‘)
 # print(ret10)  
# * strip 去除字符串前后的空格及你想去除的元素 
# ret11 = ‘   alex   ‘.strip() 
# print(ret11) 
‘‘‘ name = ‘alex‘ 
username = input(‘请输入你的用户名：‘).strip() 
if username == name :     
print(‘登录成功‘) ‘‘‘ 
# ret11 = ‘  alex   ‘.lstrip() 
# print(ret11) 
# ret11 = ‘  alex   ‘.rstrip() 
# print(ret11) 
#一： 
# ret12 = ‘asldfkjafa‘.strip(‘a‘) 
# print(ret12) 
#二： 
# ret13 = ‘asldfkjafa‘.strip(‘sa‘) 
# print(ret13) 
# ret13 = ‘asldfkjafa‘.strip(‘salf‘) 
# print(ret13) 
# ret14 = ‘asldfkajafa‘.strip(‘saWlf‘) 
# print(ret14)  
#split * 将字符串分割成列表 
# ret15 = ‘jinxin alex wusir‘ 
# ret16 = ret15.split() 
# print(ret16) 
# ret15 = ‘jinxin,alex,wusir‘ 
# ret16 = ret15.split(‘,‘) 
# print(ret16) 
# ret15 = ‘title tle tlie‘ 
# ret16 = ret15.split(‘t‘) 
# print(ret16) 
#  * 替换 replace 
# ret18 = ‘粉红色打开了粉红色级第三粉红色‘ 
# ret19 = ret18.replace(‘粉红色‘,‘嫩绿色‘,1) 
# print(ret19)  
# 格式化输出 format 
#第一种： 
# ret20 = ‘name:{},sex:{},身高:{}‘.format(‘alex‘,‘ladyboy‘,178) 
# print(ret20) 
#第二种： 
# ret20 = ‘name:{0},sex:{1},身高:{2},name:{0}‘.format(‘alex‘,‘ladyboy‘,178) 
# print(ret20) 
#第三种：键值对 
# ret20 = ‘name:{name},sex:{sex},身高:{high},name:{name}‘\ 
#     .format(sex = ‘ladyboy‘,high = 178,name=‘alex‘) 
# print(ret20)  
# 判断条件 
# name=‘123‘ 
# print(name.isalnum()) 
#字符串由字母或数字组成 
# print(name.isalpha())
#字符串只由字母组成 
# print(name.isdigit()) 
#字符串只由数字组成   s = ‘aelsdskjl‘ 
# s = s[1:] 
# print(s)  
# print(len(s)) 
#测量长度 
# index = 0 
# while True: 
#     print(s[index]) 
#     index += 1 
#     if index == len(s):break 
#for 变量 in 可迭代对象 
# for i in s: 
#     print(i) s = ‘fs4dkjla123fkj2dsa‘ 
count = 0  
for i in s:     
　　if i.isdigit():         
　　　　count += 1     
　　else:print(666) 
print(count)