1.读取一个文件，显示除了井号(#)开头的行意外的所有行

# -*- coding: utf-8 -*-

"""

Created on Tue May 28 09:37:08 2019

@author: Omega_Sendoh

"""

#打开文件

f = open("install-sh","r")

#读取文件的所有行，以列表形式存储，每行为列表中的一个字符串元素

res = f.readlines()

#循环整个列表，去除以空格开头的行的空格，然后去除以#号开头的行的#号

for i in res:

if i[0] == "#":

continue

else:

print(i)

2.无重复字符的最长子串

# -*- coding: utf-8 -*-

"""

Created on Tue May 28 10:57:55 2019

@author: Omega_Sendoh

"""

"""

定义一个空的字符串，从起始位置开始搜索输入的字符串，如果字符没有出现在wind中，则把字符加入wind

如果字符出现在wind中，则找到字符串中出现该相同字符的位置，删除该重复字符之前的所有字符

并重新加入该字符

"""

def LongestString(s):

wind = ''

l=0

for i in s:

if i not in wind:

wind +=i

l=max(l,len(wind))

else:

wind = wind[wind.index(i)+1:] + i

return l

s=input('enter string:')

print(LongestString(s))

3.制作一个密码簿，其可以存储一个网址，和一个密码，请编写程序完成这个密码簿的增删改查功能，并且实现文件存储功能。

import json

def add_info():

#打开存储文件，判断文件中是否有内容

with open('usr.json','a+') as f:

info = f.read()

#如果没有内容，创建一个字典，以字典的方式存储网址与密码

if not info:

with open('usr.json','a+') as f:

full_info = {}

net_add = input('enter your URL:')

passwd = input('enter your password:')

full_info[net_add] = passwd

print('add success')

json.dump(full_info,f)

#若文件中有内容，则把文件中的内容转换为python的字典类型

else:

with open('usr.json','r') as f :

full_info = json.load(f)

#print((full_info))

net_add = input('enter your URL:')

passwd = input('enter your password:')

full_info.setdefault(net_add,passwd)

print('add success')

#给字典中添加对象，再次写入文件中(即添加新的信息后重新更新文件的内容)

with open('usr.json','w') as f :

json.dump(full_info,f)

def del_info():

with open('usr.json','r') as f:

full_info = json.load(f)

#输入想要删除的网址

net_add = input('enter your delete URL:')

#如果该网址存在，则删除网址与密码，把更改后的数据存到文件中

if net_add in full_info:

del full_info[net_add]

print('delete success')

with open('usr.json','w') as f:

json.dump(full_info,f)

#若该网址不存在，提示网址不存在

else:

print('This URL not exist')

def change_info():

with open('usr.json','r') as f:

full_info = json.load(f)

#输入要更改的网址与密码

net_add = input('enter your change URL:')

passwd = input('enter your new password:')

if net_add in full_info:

full_info[net_add] = passwd

print('change password succcess')

with open('usr.json','w') as f:

json.dump(full_info,f)

else:

print('This URL not exist')

def check_info():

with open('usr.json','r') as f:

full_info = json.load(f)

net_add = input('enter your check URL:')

if net_add in full_info:

print('This URL password is:',full_info[net_add])

else:

print('This URL not exist')

print('you can choose: add/del/change/check/quit')

while 1:

obj = input('enter your choose:')

if obj == 'add':

add_info()

elif obj == 'del':

del_info()

elif obj == 'change':

change_info()

elif obj == 'check':

check_info()

else:

break

运行结果：